02 November, 2013

Breezair Icon EXH-130 Problems

Last Update: 15 January, 2017


Index:

Repairs to my EXH-130:

Repair 1: The Motor
Repair 2: The Water Pump
Repair 3: Tripping Circuit Breaker
Repair 4: Another Motor Fault
Repair 5: Dump Valve

Other Repairs (not a complete list):

550 Watt Direct Drive Motor
750 Watt Direct Drive Motor
DD Control Box for 1500 Watt Motor
DD Control Box 750 Watt Motor
Remote Control

Repairs for Others:

DD Control
DD Control Low Power (P/N: 110547)

Other Useful Information:

Fault/Error/Service Codes
Breezair Direct Drive Diagnostic Procedures
Cleaning Remote Control Battery Terminals
Video of a buzzing Breezair 550W Motor (internal short circuit)

Introduction


I've decided to post about my experience here as a caution about the Breezair brand of evaporative air conditioners.  Breezair is one of Seeley International's brands, they also have various other brands under their wing, such as Braemar and Coolair.

My Breezair unit has a history of repairs and I'm not the only one who's having trouble with these units, particularly the newer models with the direct drive motors.  Unfortunately, the recently released EXQ series of coolers probably aren't going to be much better.  I've already had a faulty control module from one of those in for repair and they have changed basically nothing.  They added some token surge protection to the motor drive circuitry, but thats all.  The rest of the control module is almost identical to the earlier EXH/EZH ones.

Replacement parts for these coolers are generally very expensive.  I also have some concerns about the design of the direct drive motors.

I purchased my air conditioner second hand with a known fault - motor won't run.  As it turned out, that was just the beginning.

I've owned my Breezair cooler since around January 2013.  During this time I've had to conduct a number of repairs.  This air conditioner is about 7 years old.
  • Repair 1: The motor wouldn't run.  When turned on it would just buzz/groan and wouldn't move.  The motor had developed a short circuit.
  • Repair 2: The water pump stopped running.  A little percussive maintenance got it going again, but its probably going to die more permanently soon.
  • Repair 3: The cooler started tripping the circuit breaker randomly.  It would work fine for a few days and then all of a sudden the circuit breaker trips.  Resetting the circuit breaker a couple times usually "fixed" it for a few days, then it'd do it again.
  • Repair 4: The motor developed another short circuit and damaged the motor controller IC as well.  The controller IC needed to be replaced, which I've done.  I also managed to get hold of another similar blown up motor (from an EXH-150) and repaired that temporarily while I'm waiting on supplies to attempt my first motor rewind.  If I wasn't repairing the faults myself, a new motor and new controller would cost around $1200.00 + installation.
  • Repair 5: The dump valve couldn't make up its mind if it wanted to be open or closed (it would repeatedly open and close again).  This is a known issue and replacing the two microswitches inside the dump valve assembly sometimes cures this issue.  In my case, that was not the problem.  The synchronous motor inside the dump valve was the problem.
All of this occurred within 13 months.

In case anyone is interested in knowing more about the faults described above, I'll go over some of the details in a moment.  It would be nice to purchase a new motor and other parts, but the prices of all Breezair parts are prohibitive.

Roughly speaking, a new motor will cost upwards of $550 (depending on size/wattage), a new control box (CPMD) will come in at around $500, and a new remote control is in the vicinity of $350.  A new water pump, around $150.  A new "dump valve" (sump drain valve) will cost somewhere around $250, so keep the high cost of repair in mind when purchasing a Breezair cooler.

Due to these prices and my background in electronics, I've been repairing all of the faults myself.  I also do repairs for others.  You will find my business and contact details below:


















Repair Details:

Repair 1: The Motor

The motor used in the direct drive coolers (EXD, EZD, EXH, EZH, EXQ) is a brushless DC motor (BLDC).  The motors are electrically similar to a 3-phase motor, internally wired in a "Y" configuration.

The motor had developed what I'll call a "phase-to-phase" short, meaning that there was a short circuit between two of the 3 windings in the motor.  Upon opening the motor for the first time, the first thing I got concerned about was the way in which it had been designed.  There are 3 windings in the motor, each winding consists of 20 electro-maget windings in series.  The 3 windings are all offset slightly from each other, and are all wound on top of each other.

There is no insulation, other than the very thin enamel coating on the magnet wire inside the motor to prevent a phase-to-phase short circuit.  In addition to this, I've read various documents from electric motor manufacturers that clearly state that this style of motor should not be used in humid or dusty environments.  Further more, the motor in the cooler is not sealed and as such, the windings are exposed to both humidity and dust.

I think these motors would be much more reliable if they just had a layer of insulation between the 3 windings.  It'd be even better if the coils weren't wound on top of each other.  The short circuits all seem to develop close to where the power enters and leaves the motor, and this is also where the voltage differential between the windings is at its greatest.  The design of the motor means that the enamel on the wire within the motor needs to be able to withstand a voltage differential of approximately 420V DC.  That isn't a big ask, but it also needs to withstand having dust collecting on the enamel and being exposed to moisture/humidity.

Initially, I was a little unsure about how to go about repairing this motor.  The obvious answer was to re-wind the entire motor, but I could see that would be a lot of work.  The other option was to locate the fault and either isolate it or render it harmless.  I chose the latter.

The method I used to locate the fault was to use a multimeter to determine which two phases had shorted.  The next thing I did was break the internal connection inside the motor where all 3 windings are connected together.

After doing that, I took a 12v power supply and a 50W halogen downlight and connected it up in series with the shorted turns of the motor.  The idea of the lamp was just to act more or less as a resistor, not letting too much current pass through the windings of the motor.  Without the downlight or some other current-limiting device in series with the motor, a lot of current would have been drawn and this could have caused further damage to the motor windings as they would have gotten quite hot.

I ran the light in series with the shorted motor windings for a little while and the windings on the motor started heating up.  I then used a laser non-contact thermometer to find where the motor windings were hottest.  This seemed to roughly point to the spot where the short was.

In an attempt to further verify the location of the short, I used a small fridge magnet (thin, rectangular shape) and moved it over the motor windings while still running power through them via the downlight.  This allowed me to feel where the magnetic pull of the motor was strongest and also seemed to help confirm the rough location of the short circuit.  If you happen to know of a better way to locate motor shorts, I'd like to hear about them!

The next bit gets tricky, and I don't know of a good method of doing it.  As I said earlier, the motor is a 3-phase style motor, and each phase consists of 20 electromagnet windings in series.  My plan was to isolate the fault and bypass it.  I figured that if I lose about 1 electromagnet out of 20, it probably wouldn't matter much.  After determining how the motor was wound and which direction the current was travelling around the motor, I randomly cut one wire in two electromagnets in the same phase winding (read that a few times, it should make sense.  In total, I made 2 cuts).  This allowed me to bridge over the fault, meaning I''ve probably lost about 1 electromagnet from the second phase.  The short is still there, but its semi-isolated and sort of harmless.

This got the motor going again, and it worked for about 10 months, until the motor developed another short.

Below are some photos of the motor internals.  As you can see, the 3 main sets of windings are all stacked on top of each other with nothing but the enamel on the wire preventing short circuits.  These motors would probably be much more reliable if an additional layer of insulation was placed between each phase.  The phase-to-phase shorts that this motor have developed all seem to develop at the top or bottom of the motor, not on the side.  They also tend to develop where the motor collects dust in the windings.

Here is a picture of the top of the motor.  I've never removed the PCB, however I know from experimentation that it contains the following;

  • 3 Hall Effect Sensors.  These are used by the motor control circuitry to determine the current position of the motor.  This information is then used to determine which coils (phases) to turn on next, in order to make the motor move.
  • A resistor-divider network.  This likely consists of two resistors in series, used to set a unique voltage level on one of the pins in the sensor cable.  This signal can then be analysed by the motor control circuity to determine the wattage of the motor connected to it.
  • 2 connections which go to an external thermostat switch located to the right of the PCB.  The switch is used to turn off the motor if it overheats.
In the picture below, you can see the PCB I've described above, as well as the way the 3 phases are wound on top of each other:


The side of the motor.  Each electromagnet is 3 notches wide, and each phase is offset by 1 notch:



Repair 2: The Water Pump

One day for no apparent reason, the water pump stopped running.  I gave the pump a "smack" and it was off and running again.  Its probably dying, but its been fine ever since.  I plan to replace it with a $20 submersible pump if it does die.


Repair 3: Tripping Circuit Breaker

Initially it was just a weird event, I reset the circuit breaker and everything seemed fine.  A week or so later, it did it again, so I reset the breaker again.  Over time, it started getting worse, randomly tripping the breaker every 2-3 days.

I pulled the control box out of the air conditioner and examined it.  I couldn't see any problems, and couldn't find any faults.  I re-assembled the unit and put it back into service, knowing it'd almost certainly do it again.

Predictably, it did it again.  This time the fault remained after the circuit breaker tripped.  Usually, after the breaker tripped, I could put the multimeter across the plug and measure a fairly reasonable resistance, certainly not short circuit territory.  This time, though, I measured just a few ohms.  I initially suspected some of the X2 filter capacitors across the mains, but after disconnecting those (about 3 of them) the short was still there.

I then decided to begin isolating sections of the controller circuitry by removing various common-mode chokes (pictured below).  These components basically filter noise in the power supply and help reduce interference.  It turned out that the first choke I removed was the culprit.  It was a compressed iron core with 2 sets of 20 windings on it, one winding on each half of the core, separated by a couple of cable ties.  It seems that these windings had been vibrating and had worn through the insulation on the iron core.  This caused a short circuit inside the controller, hence tripping the circuit breaker.

I found a second-hand choke among my scavenged components and re-constructed the below component, then replaced the below component with my newly made one.  The circuit breaker has not tripped since.

Here is a picture of the faulty part.  If you look closely you can see where its failed.  On the left, it failed about 4 turns down from the top.  On the right, it failed about 7-8 turns from the top:




Repair 4: ANOTHER Motor Fault

It's this fault that gave me the motivation to write about the problems with my evaporative cooler in the first place.  The motor has developed another inter-phase short circuit, close to where the power enters and exits the motor windings.

I used a different method to find the fault this time.  Instead of running power through the motor and using the non-contact thermometer or a magnet to help locate the approximate location of the fault, I used pressure.  The fault this time was intermittent, the motor would buzz/groan, wouldn't move, but when I tested the resistance of the internal windings with a multimeter (before removing the motor from the cooler), it measured about 20 ohms between any two pins on the connector.  So, I re-connected it, powered it up again... buzz/groan.  Measured it again, this time I had 1.8 ohms between two of the phases.  This confirmed a short in the motor.

I took note of which two pins had the 1.8 ohm resistance and then proceeded to remove the motor.

Once I'd disassembled the motor, I figured out which pins on the motor power connector were connected to which windings.  Once I'd figured that out, I knew which two phases were shorted.

At some point during the diagnosis, the short just disappeared.  In an effort to find it again, I started applying moderate pressure to the coils and eventually located a spot where I could apply pressure and I'd get a short circuit.  So, I knew roughly where the fault was and went about isolating it using the same method as last time, which is basically just cut some random wires and hope for the best.  It seemed to work and I was able to (after a lot of testing & re-confirming my findings) figure out how to isolate the failed winding.

Pictures of the motor on my work bench:



With the fault isolated, I re-tested the motor resistance at the power connector and it seemed to be normal, around 20 ohms.  So I re-assembled the motor and put it back in the air conditioner.  Buzz, groan.. Urrrggghhh.

I removed the motor again and using the pressure technique, found another inter-phase short.  Then, while messing with the motor again, the short disappeared.  I'd pinpointed where it seemed to be but all of a sudden I couldn't use pressure to make the short re-appear.

Applying pressure to the windings (pinching them):



So, since the short circuit just "fixed itself", I re-assembled the motor and put it back in the cooler (in a very temporary manner), and powered it back up.  Buzz, groan.  I figured that would happen.  So that re-confirmed that there was still a problem.

Further investigation of the motor windings under a magnifying glass and in good light revealed a small section of windings where the enamel had been burnt.  Applying some light pressure to that burnt area resulted in the short circuit coming back.

Here is a photo taken through a small magnifying glass of the burnt area.  That blue mark was supposed to be an arrow pointing to the burnt section:



I've isolated the above short by bridging across the coil on the outer phase rather than isolating the burnt section (which is in the centre phase).  The reason I did that was because I'd already lost a coil from the centre phase in a previous repair, so I chose to even it up a little by isolating the outer coil.

After re-assembling the motor and putting it back into the air conditioner it just buzzed, though not as loudly as before.  With a bit of encouragement the motor started running and occasionally runs correctly, but only for a few seconds, then it starts behaving as if something is commanding the motor to stop - it kind of "clunks" and jolts, then returns back to normal again a few more seconds later.

I contacted Breezair/Seeley International to see if they'd be willing to test the control unit.  I ended up getting a call from the "Victorian/Tasmanian State Service Manager", but he basically just said that the components of the cooler aren't designed to be repaired and that they have field service technicians that can come out and test the parts to determine the fault.  In other words, "go away".

Since they're reluctant to help, I continued troubleshooting.  The controller IC is an IRAMS10UP60B made by International Rectifier.  I ordered a couple and replaced the IC in the control box.

This cured the problem.  The motor controller IC contains 6 IGBT's.  They're like switches that can turn on and off very quickly.  One of the known failure modes for an IGBT is "latch-up", which means that the IGBT can turn on but can't be turned off reliably, or at all.  My suspicion is that the motor short caused damage to at least one of the IGBT's inside the motor controller IC and this in turn caused incorrect commutation of the motor.

Repair 5: Dump Valve

I bench-tested the dump valve with a 24v AC power supply and re-produced the constant open/closing problem it had.  I double-checked the microswitches inside the dump valve assembly and they were working fine.  They had been replaced previously, since I was hoping for a quick fix.

The motor inside the dump valve turned out to be the problem.  It's a synchronous motor which has the ability to run clockwise or counter-clockwise at its own will.  The problem seemed to be that, on occasion, the bushing around the shaft that comes out of the motor would catch and seize up, causing the motor to reverse direction.  Hence the constant opening and closing of the dump valve.

After further investigation, it turned out that the output shaft of the motor and the bushing around the shaft had seized, as the bushing was rotating.  The bushing isn't supposed to rotate with the shaft and would occasionally catch and seize up.  This in turn caused the dump valve to continuously open and close as when the motor seized up, it would reverse direction.

I replaced the motor with a brand new one and the dump valve now works again.  I also re-installed the original microswitches, since they were still functional and are of a better quality than my substitutes.

If you are interested in seeing the guts of the synchronous motor, I pulled apart the faulty one and took pictures throughout the process.  Here's the link:

SUH DER SD83-A Synchronous Motor Teardown

My first temporary fix (this unit isn't on the roof, so I can drain the water manually):



That's one of the pad frame clips jammed into the dump valve to keep it closed.  At this point I will mention that this is overall a bad idea.  Salt and other minerals will build up in the water as time goes on.  This will cause white deposits on your cooling pads, shortening their life expectancy.

After getting sick of opening up the cooler each time I wanted to drain the water, I decided that putting a tap on the drain pipe would be a better solution.  I got the tap and PVC pipe from a hardware store, in the garden section:




The problem with this solution is that it drains rather slowly in comparison to how it would without the tap interfering with the water flow.  Generally, I can't be bothered waiting for the tank to drain through that tap, so I just unscrew the whole assembly at the base of the cooler and let the water flow out rapidly.

The above has been a summary of all of the repairs my Breezair cooler has needed to date.

If you need repairs made to your evaporative cooler (or ducted heating for that matter), please contact me using the details on my business card below:















Other Breezair-related Repairs:

I'm often repairing evaporative cooler and heater control boards.  In addition to that, I'm often given faulty items or buy them from people who don't want them.

Below is an incomplete list of predominantly faulty Breezair components I've purchased or been given:
  • 550 Watt Direct Drive Motor (P/N: 822396)
  • 750 Watt Direct Drive Motor (P/N: 822426)
  • 1500 Watt Direct Drive Motor (P/N: 822440)
  • DD Control Box - High Power (P/N: 110554)
  • DD Control Box - Low Power (P/N: 110547)
  • DD Control Box - Low Power (P/N: 110066)
  • DD CPMD (P/N: 108988)
  • Motor Control DD (P/N: 109138)
  • Sensortouch Remote Control 1
  • Sensortouch Remote Control 2

Most of these parts were purchased knowing they were faulty, others were donated.

Repairs performed for others:
  • DD Control Box (P/N: 110066)
  • ... and many many more.
Repair Details:

550 Watt Direct Drive Motor:

This motor was repaired exactly the same way as documented above.  The motor had an inter-phase short.  The shorted section of the motor was isolated and bypassed.  After the repair, the motor was put back into service and worked for approximately 3 months.  It failed again just after the summer of 2013-2014.

Because this motor is now basically junk, I decided to experiment with it.

Firstly, I did something fairly insane and against my better judgement.  I pressure washed the motor stator (the windings) with normal tap water and a pressure washer.  That got it nice and clean.  The motor was then left to dry a little, wrapped in a towel.  It was a hot and windy day and I didn't want debris getting into the nice clean motor, hence the towel.

I then finished drying out the motor by connecting the 3 phases in series and running 12v AC through it from a heavy duty transformer (max output is 12v AC @ 13 amps).  This heated the motor windings up to about 65c.  It was left to dry like this overnight.

Experimenting further, I purchased the necessary items to build a small vacuum chamber.  It basically consists of a high-vacuum pump, a 50 litre stockpot, a 20mm thick piece of perspex (the lid) and some internal bracing rings to strengthen the pot and prevent it from caving in under vacuum.  The lid is sealed to the pot by a rubber gasket made of 3mm thick rubber sheet.  The vacuum in the chamber holds the lid on and forms an excellent seal.

What I'm doing here is partially "potting" the motor windings, using an epoxy-based compound designed for this purpose.  It has very high dielectric strength (it's a good insulating material) and it provides good thermal conductivity, which helps with heat dissipation.  It's also somewhat flame retardant.  Once dry, it becomes rigid and will prevent movement in the windings.  It will also prevent moisture and dust from coming in contact with the motor windings in the area I've potted.

The motor windings are potted under vacuum, hence the need for a small vacuum chamber.  The idea is basically to make any trapped air bubbles as small as possible, as well as helping to draw the potting compound (the black stuff) into the motor windings.

What I'm hoping to achieve by potting the motor in this way is a reduction in the failure rate.  This motor has already failed twice, so under normal circumstances, it should fail again very soon.  By potting the part of the motor where the shorts tend to occur, I am hoping that any vibration in the motor windings will be eliminated and that dust and moisture will be kept out.  I'm hoping that by doing this, the repair to the motor will last longer.

Unfortunately, this is pretty much a one-way process.  There is no way that I know of to remove the cured potting compound without further damaging the motor windings.  If the motor does fail again, it's basically junk at that point.

Due to the experimental nature of this, I also took the opportunity to embed a K-type thermocouple into the potted motor.  I did this so that I could measure how hot the potted part of the motor was getting during operation.  Basically, I needn't have bothered, as it doesn't get hot at all.





Since doing the initial potting of this motor, I have improved the vacuum chamber slightly by adding four banana plugs to the lid, which will allow me to feed power into the chamber and also give me the ability to monitor the temperature of the motor windings while doing so.

The idea is to feed power to the motor while it is under vacuum and being potted so that I can speed up the potting process by heating the motor.  I have also purchased a digital thermostat that can take a K-type thermocouple input to turn a relay on/off at a set temperature.  My plan is to use this to keep the motor windings at a pre-set temperature while they are undergoing the potting process.

This motor hasn't failed yet, but it's not being used in a cooler either.  I currently use it to test control modules with.


750 Watt Direct Drive Motor:

This motor failed the same way as the others, and was on its way to developing its next failure.  You could technically say this motor has failed in two locations.  The first location I found and repaired.  I then tested the motor and discovered seemingly random incorrect commutation.

I had my doubts about the controller I was testing the motor with, so I swapped it for another known-good one.  The problem persisted, and upon further examination of the motor, I found a second area where the enamel wire has been burnt.

I haven't repaired this motor yet.


DD Control Box for 1500 Watt Motor:

This control module needs a new motor controller IC, since it has failed rather explosively.

Here is a picture of two motor inverter ICs.  The top one has failed explosively.  The IC below it is physically in-tact, but internally has one or more failed IGBT's:




DD Control Box 750 Watt Motor:

This one might scare you.  To be honest, it worries me.

I purchased this controller recently.  It's another case of a common-mode choke failing.  The failure is similar to the one documented above, which occurred in my cooler.  Fortunately for me, mine didn't catch fire, but this one did!

I've repaired this controller by using the filter from another controller that was damaged beyond reasonable repair. The common-mode choke shorted from active to neutral through the toroidal core.  My best guess is that this occurred due to vibration of the windings on the core.  The short circuit/arcing caused the plastic cable tie to get hot and catch fire, dripping flaming plastic drops onto the components and parts of the controller casing below.

The collateral damage was the two wires that go to the circuit breaker and the mains power socket.  I decided to replace the damaged wires with ones from a parts controller.  The power socket was not damaged enough to warrant replacing it.

Here are a few pictures from the insides of the controller.  First up, the toroidal filter that caught fire:



Burnt spots inside the controller casing.  This appears to be where flaming drops of melted plastic from the cable tie around the base of the toroid have dripped down onto the bottom of the controller casing:



The image below shows heat damage to a capacitor close to the toroidal filter that caught fire.  It also shows damage to the two brown cables that go to the circuit breaker, as well as minor damage to the mains power connector (the pitting around the edge is not supposed to be there):



The scary thing is that this failure could happen at any time.  The common-mode choke (filter) that failed in this case is continuously powered up by the mains.  It doesn't matter if your cooler is turned on or off at the control panel.

Here is a close-up of the burnt area of the common-mode choke:



In the picture below, which is otherwise the same as above, I've highlighted where the copper turns of the common-mode choke have melted away and gone open-circuit:



Remote Control:

I recently purchased a faulty Breezair Sensortouch remote control.  It was advertised as "New" and the description said that it would freeze after the first command.

I purchased it not being sure what its problem would be, but I had my suspicions.  I was hopeful that it wasn't a fault in the microcontroller inside the remote control, since I couldn't replace that if it died.

There was no evidence of battery electrolyte leaking onto the circuit board, however, one of the pads for the buttons on the front of the remote was measuring as low impedance (about 100 ohms) while all the others were measuring about 700k.

Due to there being no evidence of any sort of contamination to the circuit board, I traced where the pad was connected.  One side of the pad was connected to battery negative, while the other side of the pad was connected to a HEF4021 IC and another component in a SOT-457 package labelled as "B2" (which I'm suspecting is an NXP PMEM4010PD).

Since I had the HEF4021 chips in stock and they're easy enough to replace, I did that, suspecting that the chip had maybe been damaged by static or something like that.  It made no difference.

Not having the "B2" part in stock, I de-soldered it and then re-checked the resistance across the pad.  It changed, but not much, so there was still a low impedance short somewhere, and the only place left was the pad itself.

Here is a close-up of a couple of pads.  They are gold-plated contacts, in a fork configuration:



Somehow, one of the pads had become conductive and was telling the remote control that someone was pressing and holding the economy button.

I cleaned the circuit board with PCB cleaner multiple times and it didn't fix it.  Since the obvious failed, I decided to use a clothes pin to dig shallow trenches in the gaps between the gold fingers on the pad in question.  This resulted in the resistance of the pad increasing substantially and cured the problem.  The remote control is now fully functional.

As a precaution, I also cleaned the button membrane with dishwashing detergent and an old toothbrush, washed it off and then thoroughly dried it.  For completeness, here is what the back of the button membrane looks like.  When you press the buttons on the remote, the conductive pads make contact with the gold fingers and this lowers the resistance of the pad.  This in turn is detected by the remote as someone pressing a button:




Repairs for Others - DD Control (P/N: 110066):

I was contacted by someone who had a faulty control unit.  He provided me some high-resolution pictures of the visibly burnt parts of the unit and I basically did a remote diagnosis of the problem from the photos I'd been provided.  Obviously, I couldn't check everything or poke around at all the components I wanted/needed to.  He was in Perth and I was in Melbourne.

The person in question ended up sending me his controller.  My plan was to take a look at it, do a proper diagnosis and attempt a repair.  If the repair failed I was prepared to cover the cost, even though I didn't really want to.  I figured that if the repair failed and the controller went up in smoke when I tested it, then really, I'd failed in my attempt to repair the unit and my customer shouldn't be the one to pay the bill in that case.

So I did the diagnosis, ordered parts, waited in excess of a week for them to arrive, kept the customer informed throughout and eventually did the repair.   Unfortunately, I was hit by a power company screw-up at this time and I wasn't able to test the repairs to my own satisfaction.  I ran his repaired controller off of an inverter for 5 minutes to test it.  Normally, I'd have run it for much longer, an hour or more, just to make sure it was going to be OK once it was put back into service.

I've since found out that the repaired controller is working well.  I'm happy that I've managed to save someone $600 or more.

This controller blew up a number of parts.  In this model, there were two MOSFETs that needed replacing.  One had gone permanent short-circuit, the other was still testing OK but in my opinion I couldn't trust it, since they were both wired in parallel and so they both may have been damaged when the fault occurred and the current-sense resistor was burnt out and had gone open-circuit.

The cause of the fault remains unknown.


DD Control Low Power (P/N: 110547):

This controller suffered a failure in the Power Factor Correction part of the controller.  There was evidence of arcing across the PCB beneath the MOSFET, however there was no trace of what caused it.

The MOSFET still tested OK, but was replaced as a precaution.  Ceramic capacitor C151 was replaced as it had been permanently discoloured on one side by the arcing.  The two surface mount transistors were also replaced, mostly as a precautionary measure but motivated by the fact that I couldn't test one of them in-circuit.

Below is a picture of some of the damage.  To the left you can see R102 and R103.  In the centre is the location of the MOSFET and you can see something nasty has happened.  I strongly suspect that arcing had developed across the drain and source pins of the MOSFET, due to the PCB having become contaminated.



Other Useful Information:


Fault/Error/Service Codes:


Below is a list of the fault codes and briefly what they mean:

Fault Code 1: Communications problem - check communication cable between wall control and cooler for damage.

Fault Code 2: Water not detected at salinity probes (usually within 8 minutes) - water turned off, solenoid valve faulty, no power to solenoid valve (should be around 24V AC at solenoid valve terminals when cooler is in cool mode) or faulty (open-circuit) salinity probes.

If you receive fault code 2 within 10-15 seconds of turning the cooler on, then you likely have an EEPROM corruption problem (see fault code 3).

Fault Code 3: EEPROM Failure or Corruption.  The control board stores a small amount of data related to settings for the operation of the cooler in an EEPROM chip.  If this data becomes corrupt, you will often receive fault code 3.  This fault code isn't documented but it is repairable by replacing and/or re-programming the EEPROM.

Fault Code 4: The cooler wanted to drain the water from the "tank" at the bottom of the cooler but after waiting 4 minutes, water was still detected by the salinity probes.  This suggests either a faulty dump/drain valve (not opening) or a blockage in the drain pipe.

Fault Codes 5 & 6 aren't documented and I'm not sure if they're even possible.  If you have either of these fault codes then please get in contact with me.

Fault Code 7: Mains power supply frequency is incorrect.  In Australia, we have a nominal 50Hz power supply frequency.  Fault code 7 will be produced if the mains frequency is outside the limits of 46-54Hz.  This can be caused by contamination to the circuit board in the control module (eg. spiders and other insects), generators or possibly even faulty solar inverters.

Fault Code 8: A brief power failure has been detected.  Nothing to worry about in general.


Breezair Direct Drive Diagnostic Procedures:

I've written a short document detailing some procedures that can be used to diagnose your Breezair evaporative cooler.  This document applies to direct drive models only, such as the EXH/EZH/EXQ/EZQ series.

The goal of the document is to establish that you have communication between the wall control or remote control and the cooler on the roof and then to determine if you have a defective motor or control module.  The document is aimed at coolers that have motor or fan-related faults, as these can be difficult to diagnose correctly.

You can download the document from the following link:

Breezair DD CTRL Motor Test Procedures.pdf


Cleaning Remote Control Battery Terminals:

I've just had to clean the battery terminals of my original remote control.  One of them in particular had turned completely green.  This was caused by the leaking alkaline batteries.

Normally I'd take a rotary tool and carefully grind it off and make the terminals look pretty again. 

This time I tried vinegar.  It may have worked a little, but it wasn't good enough.

Next, I thought I'd try a different acid.  I got a small amount of Ranex Rust Buster (phosphoric acid) and drowned the terminal in that.  It immediately started fizzing and ate away the corrosion.  The contact it left behind (on the left) is pictured below:



While I was soaking the terminal in Ranex, I started wondering if the Ranex would do any harm to the plastic case of the remote.  So I put some on a cotton bud and rubbed it on the plastic where the old batteries had left a rust stain.  It cleaned up well.  Unfortunately I don't have a before pic, so I did a similar this to the battery cover for the remote.  Here are the before and after photos:

Before:



After:




Video of a buzzing Breezair 550W Motor

Below is a video of a Breezair 550W Direct Drive motor with an inter-phase (or phase-to-phase) short circuit.  It was the common type of short circuit that these motors tend to develop.

This motor has since been repaired (for the second time) and seems to be running fine again.  Running the motor, knowing its got a short circuit in it is a risky thing to do as it could damage the controller, but I did it anyway for the sake of making the video and potentially helping someone diagnose their cooler in the future.

No controllers were harmed in the making of this video...

video


All trademarks are the property of their respective owners.


A Quick Note About Comments

Firstly and most importantly, make sure you check the "Notify me" check-box before submitting your comment if you want to be notified when I reply to you.  If you choose "Notify me", you'll get a copy of my reply to your comment e-mailed to you.

I do my best to promptly reply to all comments left below.  I'll delete comments that don't provide any value to the general audience but just know that it's not personal.  I read every comment and will generally reply to every comment.  I often delete my own replies if they provide little value to other readers as well.

As such, you may notice that I've replied to a person but they appear not to have followed up from that.  It was most likely because their comment was along the lines of "Hi Rob, thanks for your advice.  My cooler is now working again".  While I appreciate these comments and will often reply to them as well, I will almost immediately delete my own reply and the "thank you" comment, as they don't provide any useful information to anyone.

The reason I do this is to reduce clutter in the comment section.  If you've read the entire blog up until now, you've already been here for quite a while.  There's lots of comments below with lots of good information and troubleshooting advice, but if you read it all you'll be here a fair while longer, so the less clutter in the comments, the better.

45 comments:

  1. Hello Robert,

    I'm an ex Qantas ground engineer in the field of aircraft component test equipment (1959 -74). I'm absolutely impressed with your report and attention to detail. Easy to follow.

    You've adapted some really brilliant strategies to get things working however, there's one thing I believe might help for the future.

    You mentioned interwinding shorts at the top and bottom of the windings but not at the sides. I remember similar problems from my Qantas days. Believe it or not, the shorts come from the deposition of microscopic amounts of "hard" dust in the atmosphere which accumulates on the windings.

    As you are no doubt aware, windings are in themselves small electromagnets and without a hard setting varnish to encapsulate them they actually vibrate, wearing the enamel coating from the wire and allowing turn to turn bridging to occur. Simple gravity causes the dust particles to be "shaken" from the windings at the sides.

    Aircraft components adopt highly critical technology because of the need to save every gram and cubic cm of space for lightness, This necessity does away with the luxury of inter winding insulation. In order to overcome the problem of winding movement wearing away the enamel, all electric motors, new and rewound were dipped in a conventional winding varnish but inside a vacuum oven to remove air bubbles. Once the varnish was set, nothing moved and the weight saving using this method was considerable over hundreds of motor units per aircraft. A real pain in the backside to implement. Of course, simply dipping a commercially made stator in air drying varnish would no doubt do the job, Unfortunately quality in manufacture goes on a holiday in competitive manufacturing environments.

    Horizon Control.

    Mt BreezAir RC unit packed it in after the Mallory batteries decided to leave their contents inside the controller. Time for the metho/toothbrush routine. which got it kind of working again. Probem remaining was that the controller worked but the LCD display didn't so it was like hit and miss braille to get the aircon working.

    I decided to have a look inside the RC to see what could be done. I discovered while the unit was in two halves with the batteries installed that if I twisted the half with the LCD display, some of the characters would show, allowing me to use it. So that's how it is ATM because I'm not paying $380 for a remote that has virtually zero innovative technology.

    Hope the comments have helped you and others

    Richard Crawshaw,
    Perth, WA

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    1. Hello Richard,

      Thanks for your comments, that was interesting, especially the info about the "hard dust" :)

      I found that the leaking batteries damaged some resistors and made them go open-circuit (some failed after the first bunch of repairs were done as well). The electrolyte also seemed to eat PCB tracks and in my case it also ate/corroded the legs off a couple of ICs as well.

      It also managed to stuff up my keypad, which is on the other side of the board. It turned all the nice golden pads into brown/black looking pads, which then also became conductive (as if the button was permanently pressed).

      If you haven't already, maybe check the condition of the pads under the LCD. Its also fairly trivial to trace back all those tracks to the MCU (main chip) and you could then check the conductivity from the LCD pad to the IC pin it goes to.

      You could also check all (or as many as possible) of your through-hole vias, the battery electrolyte can cause them to go open-circuit and there are a number of those around the LCD (at least in my remote).

      Rob.

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  2. I have an EXH170-H Breezair cooler and everything works except the motor. There is no error code on the control pad but 2 green and 3 red lights flashing in the control box inside of the unit. Has anyone suffered the same problem and what is it?

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    1. Hello denrose,

      You won't get an error code for any motor related problems, so that part is normal.

      Try setting your cooler to vent mode, then look at the lights on the main control box in the cooler. If it clicks but none of the lights come on on the left hand side, then the controller probably has an internal fault.

      If you turn the cooler on in vent mode and the motor makes a buzzing or groaning noise, then the motor has probably developed an internal short circuit.

      I can repair some of the control boxes that have failed, but it depends on the part that failed and the extent of the damage to other circuitry.

      You may e-mail me directly and we can troubleshoot further if you wish: rmdavidson (at) gmail (dot) com

      Regards,
      Rob.

      Delete
  3. Hello Rob,

    I also have Breezair Harmony EXH210 installed 2008. After 6yrs used it's now showing problems. When you switch it "On" the wall controller displays [Auto-Cool-preparing to start]. After few minutes when the pads are saturated the motor fan starts providing cool breeze air.

    However after about 10-20 mins it shuts down. This is an ongoing process and I finally decide to investigate. At the Main Cooler control box (110554) I looked at the diagnostic indicators. The DIAG red LED flashes twice and the SAL red LED flashes once. Do you know what that refers to? How & whats the fix?

    At the moment we can use the cooler in Man-Cool mode.

    ReplyDelete
    Replies
    1. Hello Eddy,

      My original reply disappeared, so here we go again...

      I suspect your problem has something to do with the salinity probes. If the probes are starved of water, the cooler will turn itself off after a while.

      The reason for this, going from what you've told me, is probably not due to any fault of the salinity probes, but rather a faulty water inlet solenoid (not opening fully and restricting water supply to the cooler) or a faulty float valve.

      I would suggest you turn the cooler on, in cool mode, and then go up to the roof and watch what its doing. Note if the tank is slow to fill, and note whether the pump drains most of the water from the tank when it turns on. If it does, you have a problem with the water supply to the cooler - most likely the inlet solenoid (located underneath the cooler).

      If the salinity probes become starved of water, the cooler detects this and turns off after a short time.

      You may also get error code "2" on the wall controller in this situation. It is basically hinting at a water supply issue - aka a restriction in the water supply to the cooler, preventing the tank from filling and staying filled when the pump first turns on.

      If you have a different error code on your wall control, please let me know what it is and I will tell you what it means.

      Regards,
      Rob.

      Delete
  4. Hi Rob,

    I don't know what happened to my reply last night. Here's another one.

    Well, you confirmed my suspicion that it is a water issue and not the electronics.

    After running for few minutes the cooler does shut down and the wall controller flashes "Service and error code 2".

    As you suggested i went up the roof and observed how the water enter and fill the reservoir. I took the wall controller with me and using a short test lead i plugged the wall controller to the the Main Control Unit.

    I press the "ON' button and the inlet solenoid energized and let water through. However the rate of flow is slow and restricted. This explained why the "preparing to start" cycle is taking ages.

    It took more than 5 mins for the water to reach the required level and eventually the float switch stops the water entering the reservoir.

    At this point the Salinity probe are shorted via the water and the Tornado water pump start pumping water through the pads till they saturate. After awhile the fan starts and blows cool air inside the house.

    As the water pump keep pushing water through the pads the water in the reservoir decreases, the water level then drops and the Salinity probe is now open circuit. Since its taking ages to replenish the reservoir with water (to short-out the Salinity probe) the Main control unit then see this as a problem and hence stops the cooler from operating.

    When I find time I'll have a look at the inlet solenoid and check what's causing the problem. Maybe you can give me some tips.

    I'll keep you posted of the outcome. BTW thanks for the prompt reply.

    Regards,

    Eddy

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  5. Have just found my EXH210 is draining water all of the time, got on the roof and I have the dump valve cycling up and down. The unit is only about 3 years old and it replaced an EXH10 which was 20 years old and NEVER gave any problems. I am planning on putting a small plastic tap on the drain line (it is well sealed) and restricting the drain flow to about 10 litres / hour. till i get time to strip the dump valve.

    ReplyDelete
    Replies
    1. Hello Squidlips,

      Thank you for sharing your story.

      As you may be aware by now, the older coolers are generally more reliable than the newer models. Lets hope that changes at some point.

      If your cooler is only a few years old like you say it is. then it is likely still under warranty! I believe you should have gotten a 5 year warranty as standard when your new cooler was installed.

      So, maybe find the paperwork for your cooler, the receipt, etc and give a Breezair service company a call, and get it done under warranty.

      Alternatively, if you don't want to do that for some reason, or if you find your cooler is out of warranty, I do sell the motor you most likely need and the microswitches, so that you can refurbish your dump valve.

      The bad news is that I only have 1 motor left in stock and there are supply issues which is preventing me from getting more of them for the time being. At this stage, the earliest that I will have any more motors will be mid-March, but there are no guarantees.

      So, if you need one, act quickly. Very quickly.

      Delete
  6. hello robert,
    i recently installed a relatively new ezh breezair evaporative cooler. the other day i had turned it on which was all good for about ten minutes until the fan stopped working. any ideas as to why that might of happen?
    apart from that everything else is working fine,
    the tornado pump is working, the dump valve is working, the float and solenoid is working just not the fan. i checked the windings on the fan and they all checked out fine at 18 ohm across all windings. could it be the circuit board which is faulty?

    cheers
    Adrian

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    Replies
    1. Hello Adrian,

      Based on what you've told me, I'd suspect that the board has probably failed. 18 ohms across all windings is about right.

      I'd suggest you turn on the cooler and put it in vent mode, then have a look at what the LEDs on the control module inside the cooler are telling you. There are 6 LEDs all up, the ones that matter in this case are the 4 LEDs on the left hand side.

      With the cooler in Vent mode, check that the LED labelled "POWER" comes on, at the very least. The "THERMAL O/L" LED should also come on. If there aren't any LEDs on, then the board has failed.

      The other thing to check is that the plugs for the motor power and signal cables are both plugged in properly. If there's a bad connection anywhere, it will most likely prevent the motor from running.

      If you need more info just let me know, otherwise you can call me on 0429-235-780 and we can go through some troubleshooting. If you decide that you want the module tested and/or repaired, I can also help you with that.

      Thanks,
      Rob.

      Delete
  7. So I bought an EXQ / EXS (?) unit with Magiqtouch controller for my lad last November and he has just had it installed today.
    So I ask how its going and he said it ran for 10 minutes and it just shut down. )-:
    Evidently he called the installer and he came back, checked everything and all lights etc were ok with no faults registering. It just wouldnt run.

    I haven't been around there but will probably get to see it tomorrow night, any suggetsions, just in case it may be something simple??

    We'll be chasing up warranty tomorrow morning.

    Cheers!

    ReplyDelete
  8. Hello Squidlips,

    I'd suggest that it'd be best not to play with it at all and let it be delt with under warranty. I wouldn't do anything to it that could give Seeley a reason to void the warranty.

    If the cooler doesn't respond to anything that you do on the Magiqtouch controller (eg. if you put it into cool mode and it doesn't do anything at all, eg. doesn't close the dump valve, doesn't let the water in) but the Magiqtouch seems to operate normally, then it could be a communication issue. The Magiqtouch can be reset to factory defaults using the reset button on the back (using a straightened paper clip, press the button for about 5 seconds). The Magiqtouch will ask for a PIN code, which is 7378. From there, you can tell it to reset the entire system. The Magiqtouch will reset itself and take you to the configuration wizard, which you need to complete.

    That said, it may not be a comms issue, it could be something else. Probably best left for a qualified tech, due to the warranty issue.

    Regards,
    Rob.

    ReplyDelete
  9. Thanks Rob,
    AS you say as its under warranty We'll let Sealey fix it.
    Its a bit dissapointing it's failed 10 minutes after 1st running.
    We're having 40 degree days and it is stinking hot.

    I bought it as a wedding present for them so it has turned out a bummer.

    I'll let you know what they find.

    Cheers, Squid

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    Replies
    1. Thanks Squidlips, it'd be good to hear whats happened.

      Unfortunately they didn't really make any improvements to the EXQ control modules. The circuity is almost identical to the models of the last 12 years or so (EXH/EZH series). All they've done from an improvement perspective, is add some basic surge protection to the motor control circuity.

      They changed the communication interface circuitry as well, but thats unlikely to improve reliability.

      Regards,
      Rob.

      Delete
  10. Hi Rob, Brilliant site. I have an EXH210 and the water pump stopped working, I have replaced the pump and still no go, everything else works, also the diagnostic leds on the control box (110554)are all normal (referred to Installation manual). Can you offer me any advice?.

    Karl

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    1. and I have replaced the water sensor.

      Karl

      Delete
    2. Hello Karl,

      If you've replaced the pump and the salinity probes then as long as water is coming into the tank and immersing the bottom parts of the probes in water, then the control module has probably failed.

      If water comes into the tank, the next thing to check would be what the SAL LED indicates. If it is solid on, with water in the tank, then either the salinity probes are faulty, not properly connected or the control module has failed. There were some older models of the control module that weren't able to detect extremely pure water as well (e.g.. rain water)

      Once the probes are immersed in water, the SAL LED should be mostly off, with the occasional blink.

      If the salinity probes don't detect water, the control module won't turn the pump on. If you have a hard-wired wall control, you'd also get error code 2 on the display.

      Hope this helps,
      Rob.

      Delete
  11. Hi Rob, I'm impressed by this website, full of useful information. We have an ES 125 unit, quite old but, apart from a new pump, it has been reliable until now. It runs for some time and, without notice, trips the circuit breaker on the main fuse board (i.e. not in the unit). Resetting the circuit breaker gets it going again for quite a while until it again trips the circuit breaker. It sounds similar to the fault you fixed with chokes (repair 3) on the EXH-130. Being a different model and one that requires an expensive upgrade if the controller is faulty, is the choke problem a likely fault and can you fix it. Do you make house visits?

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    1. Hi DJF,

      Apologies for the long answer.

      The ES series control modules do have a choke in them, but its failure wouldn't cause the breaker to trip.

      If you have the older-style control module (grey box) then it would have a fuse in it that would probably blow before the breaker in the distribution board tripped.

      I'd suggest you check the power cable itself for damage, especially where it goes into the dropper (often a large metal duct on older systems). There should be a rubber grommet installed where the power cable goes through the metal dropper, if it has perished or become displaced, then the sharp metal edge of the dropper could wear through the cable and cause a short circuit. The dropper could potentially be live, hence why you need to turn off the mains power to the cooler (and preferably unplug it) before you start the inspection.

      There are a number of other questions that might give some clues to the problem:

      1. Did the breaker trip before the pump was replaced?
      2. Does the breaker ever trip when the cooler isn't running?
      3. Does the breaker trip when the cooler is in Vent mode?
      4. Did you experience any power surges (that you know of) prior to the first trip?

      If the answer to question 1 is No, then the new pump may be the cause.

      If the answer to question 2 is Yes, then that rules out the fan motor and pump. It doesn't rule out a fault within the control module or mains wiring though.

      If the answer to question 3 is No, then that suggests the pump may be the problem.

      If the answer to question 4 is Yes, then that gives some credibility to the fault being in the control module. This is because the older (grey box) control modules had some basic surge protection built-in. If the surge protection device (a MOV) has been damaged, then this could cause the circuit breaker in the distribution board to trip. It wouldn't cause the fuse in the control module to blow though, as the fuse doesn't protect the surge protection device.

      If you have a newer cream/off-white-coloured control module, then you'll have a circuit breaker inside the cooler instead of a fuse, and most of what I've written here goes out the window. The reason being is that those circuit breakers don't tend to trip very quickly when there's a short circuit, in my experience, it's usually the breaker in the distribution board that trips first. They also removed the surge protection (MOV) from the cream-coloured control modules, so thats one less item that could cause the tripping.

      Hope this helps or at least gives you something to think about.

      Regards,
      Rob.

      Delete
  12. Hi Rob, great blog! I have a coolair Cpl unit that uses a Braemar CPMD Control Box and I now get frequent #07 error codes. A bit of searching revealed the error relates to out-of-tolerance 50hz supply. Living in Perth I assumed the supply was at fault but now not so sure as the fault is occurring more often. I have replaced many of the parts inside the 10 year old unit including the direct drive motor(always amazed at the cost of fairly basic items) but never had a look inside the control unit. I have an electronics background so would appreciate your thoughts.
    Cheers
    Eddie

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    Replies
    1. Hi Eddie,

      Fault code 7 is certainly out-of-spec 50Hz. The mains frequency needs to be between 46-54Hz.

      I've never had to repair a Breezair control module that was generating fault code 7 erroneously. However, my first thought would be to check for things such as bad solder joints around the chokes on the board and around the mains power connector and the transformer, in case there's some arcing going on which could in turn affect the mains frequency that the rest of the control module sees.

      Short of having an oscilloscope and a differential probe, I doubt you could measure the mains frequency too easily. Some multimeters will measure frequency, but you'd want to check if it's capable of doing that before trying it. It could be designed for low voltage logic rather than 240V AC. If you have a multimeter with such a feature, then the manual would tell you.

      Other possible sources of incorrect mains frequency might be arcing somewhere between the distribution board and the power outlet in the roof for the cooler, maybe also a faulty solar power inverter, faulty street transformer or if you use a generator, then that'd be another potential source of the incorrect frequency.

      Clocks in things such as clock radios, microwave ovens and electric ovens often use the mains frequency to count time. If you have clocks in your house that are either gaining or losing time then that could indicate that the mains supply to your house is the problem. This won't apply to all clocks, as not all use the mains frequency to count time, but basic alarm clocks often do.

      It would be good to know if you experience the fault only when the fan is running or if it happens randomly even if the cooler hasn't been turned on at the wall control/remote. I'm not sure if the control modules monitor the mains frequency at all times, or only when the cooler is actually running, but I'm tempted to find out by doing a little experiment.

      Regards,
      Rob.

      Delete
  13. Thanks for the suggestions. Interestingly I did consider the impact of my solar panel inverter (such as what happens when the inverter shuts down at night vs when the fault typically occurs) so I had better measure the mains frequency first. It's currently too hot to risk taking the cooler out of service but will let you know what I find once the weather cools a little

    ReplyDelete
    Replies
    1. Hi Eddie,

      If it only happens during the day then maybe shutting down your solar inverter/array would be a good first step, just to rule it out.

      Regards,
      Rob.

      Delete
  14. Well the air con failed completely Saturday morning so I was forced to act rather than wait for cooler weather. I removed the control unit and a quick inspection of the connections area revealed a cobweb! So I opened the unit (not easy given it has many one way tangs to hold open) and found several dead spiders inside. I have had mixed success with surface mount cleaning so I started with a simple and liberal blast of electrical cleaner and reassembled. It has been running ok for 48hrs so fingers crossed. The unit has no significant protection for such a hostile environment and depends entirely on the principle of water follows gravity - thus allowing spiders easy and cosy digs. The board is full of surface mount devices with no moisture or dirt protection. Happy to send a photo if you are interested.

    ReplyDelete
    Replies
    1. Hi Eddie,

      I've seen it all before, numerous times, though usually the cobwebs don't cause a problem. The later Bonaire boards and the Brivis evap boards that I've worked on have been protected with a conformal coating.

      Regarding cleaning the board, isopropyl alcohol generally works well, but it can dissolve some protective coatings.

      I don't generally recommend people use cleaning chemicals unless they are specifically made for PCB cleaning. This is because some chemicals leave behind a residue, which over time collects dust and becomes conductive.

      I often use a clean paint brush dipped in methylated spirits to clean boards, but sometimes end up using a proper chemical designed for cleaning PCBs. It depends a bit on what I'm cleaning up.

      Some other potential issues with cleaning boards are that you could get the chemical inside the windings of a transformer or inductor. This may cause problems later on (eg. corrosion, shorts) or compromise the insulating properties of the transformer.

      A dry brush could also create static which could damage sensitive components on the board. Damage caused by static discharge doesn't always show up immediately.

      Compressed air isn't completely safe either. Air moving at high velocity can build up a static charge as it leaves the air gun and also as it flows over the insulating parts of the circuit board. Air lines often have moisture in them as well, and sometimes the watery droplets contain traces of oil.

      A soft-bristled anti-static brush and proper grounding would probably be the safest method to clean dust and cobwebs from boards, but most people wouldn't have such a brush. You should also try to avoid putting oily fingerprints all over the PCB.

      Regards,
      Rob.

      Delete
  15. The cobweb was fairly substantial inside the unit, more like a nest - not to mention the spiders dead bits across the board. I am also a fan of methylated spirits having saved a few devices that were dropped in water by liberal use of the stuff.

    Thanks again for your advice

    ReplyDelete
  16. Hi,

    I have a EXH170 installed 2010 has been very good till now with only a solenoid replaced. I had been advised to get the pads replaced and the fan cleaned.
    So I went ahead and had a company do that. The very next day my husband could smell smoke so turned it off. When we went to restart it the rcd tripped. When the company came back the next morning he checked everything and couldn't find a fault and managed to get it to run woth tripping. We had the air con going all day. I did notice that the air con didn't seem to be blowing air as strongly as it used to. Turned off that night - the next day same thing the rcd tripped after only a few minutes.
    He came back on the monday. Air con wouldn't trip on VENT only when switched to COOL. He said that the problem was with the control box (110547)
    The company sent me an email saying it was the water management system and to do with the salinity blah blah. I said I think someone else should come and look first. There other tech rang me and said def water mgt system common problem with an ES unit. I said I don't have an ES it's and EXH!! Completely diff systems.
    The batts they installed are also not what Seeley recommends they put in Celdek when they should be Chillcell. They do seem to be the right size but the box says for ES and EM models. Most other techs say the motor has to be removed to clean fan - they didn't do that.
    So could the tech when he was servicing and cleaning have damaged the control box?
    He also had power and water on while doing the maintenance.
    Has he reset the motor power wrong and fried the contol box? Just seems strange that everything was fine the day he got here than bam it's fried. It also looks like they have opened the part of the control box that isn't supposed to be as the plastic is damaged from maybe a screwdriver.
    Helen

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    Replies
    1. Hi Helen,

      I think they've taken you for a ride, honestly. A few things you've said above are alarming.

      Firstly, if your evap was installed in 2010, it shouldn't require new pads this soon. They should last 15 years fairly easily. Unless they were structurally compromised (falling apart) or covered in mineral build-up (lime scale, etc) then they shouldn't need replacing. Regarding the Celdek/Chillcel issue and the box saying they're for EM/ES, I wouldn't worry. To my knowledge, the size and thickness of the pads has remained constant until very recently.

      Without going into too much technical detail, there's almost no chance that the water salinity system in the EXH series of coolers could trip an RCD. It's near on impossible.

      Regarding the technicians you've had out, if you're going to get a different tech, get one from a different, totally unrelated company. The first technician has almost certainly briefed the other one.

      It's common for the solenoid valve to fail, nothing abnormal there. The fan needing cleaning, maybe, but unless you live in a dusty area (eg. on a dirt road) or use the cooler quite a lot, then I have my doubts that it was really required.

      You can't change/reset the motor power. In an EXH model, the motor control circuitry detects what size motor is plugged in and runs it accordingly.

      So lets get to the main issues now. The RCD tripping is a concern, as is the smell of smoke.

      Regarding the RCD tripping, there's a fault that can occur within the control module (in the pump circuitry) that can cause this. It will also be more likely to occur in a humid environment (eg. after the pump has been running for a while).

      If you've got the problem I think you do, then having an RCD will reduce the amount of damage being done to the control module when this fault occurs. The problem could also be the pump, but it's not very likely.

      Regarding smelling smoke. If you've read the blog you'll know that these control modules can and do catch fire occasionally, however, once they do, they don't generally work afterwards. With the RCD issue, I doubt you'd get to the point of being able to smell anything before it tripped if it were the pump circuitry causing it. I wouldn't be too surprised if the smoke smell was from something outside and just got sucked in through the cooler.

      I hope this helps. If you'd like to have me take a look at your control module, test it, repair it (if necessary) then please get in touch directly. You can call me on 0429-235-780 or see the business card image for my email address.

      Regards,
      Rob.

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  17. Hi Rob I have a similar problems as some of the above no motor turning when we use our remote control. My unit is a Breezair EXH 130 with a remote control install 2005. So had a guy come out and said motor is u/s so I did some research and I have about 17.5 ohms on each of the three pins for the lead to motor. My lights are marked differently O/L, Sensor 1, sensor 2 and sensor 3, plus daig and SAL. On the module the only light that is on is sensor 2 in the row of 4. I had a motor replaced in 2008. Any help would be good thanks Michael from Perth

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    Replies
    1. Hi Michael,

      If you unplug the 3-pin motor power cable first, but leave the flat sensor cable plugged in and turn on the cooler in Vent mode, you should be able to move the motor by hand and the other sense LEDs should flicker when you do that. If they do, then it would tell you that the sensors inside the motor are probably OK.

      I can give you a test to do with your multimeter which may help determine if the control module has failed, but send me a direct e-mail as I need to send you the instructions.

      The test you've done, measuring the ohms of the motor windings is good, but doesn't always reveal the full picture. Sometimes motor faults only occur at high voltages, such as when the motor is running, as the insulation in the motor can degrade.

      Regards,
      Rob.

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    2. Yeah Rob turned it over with plug disconnected the top 3 LEDs flashed when I turned it. can I text you my email rather than post it. What's the difference with the Led light names on the older units, such as sensor 1 etc?

      Michael

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    3. Hi Michael,

      The SENS 1, SENS 2 and SENS 3 LEDs on your control module refer to the hall effect sensors inside the motor. The motor has three of these sensors, the LEDs will flash briefly as the motor turns, or appear to be always on when the motor is actually running. The sensors tell the control module which windings in the motor to activate next, as well as the speed that the motor is running at.

      The O/L LED means overload, so for instance if the over-temperature sensor in the motor detects that the motor is running too hot, the O/L LED would turn off and the motor would stop.

      The newer control modules have different LEDs (Power, Hall Effect, Speed, Thermal O/L). Those LEDs provide better diagnostic information than the SENS 1/2/3 do. "Power" means that the motor control circuitry has power, "Hall Effect" basically just indicates that the motor is running (ie. the Hall Effect sensors are working), "SPEED" will be on solidly if the motor is running at the correct speed (RPM) for the speed selected on the wall control/remote. If it's flashing then it indicates that the motor is running either too fast or too slow and it'll eventually shut off the motor if the speed remains incorrect.

      Regards,
      Rob.

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  18. G'Day Rob,

    Great site, thanks for all yout work and help you provide.

    My Breezair ES 145 has had a little dummy spit. We had a power spike last Friday when the Torrens Island power station had a fire in one of their turbines. It cause lights to flicker all over Adelaide.

    When we got home from work the EAC was running but there was no display on the wall control. I was unable to trun it off. None of the buttons seemed to have any effect.

    We hadn't left the EAC running so we suspected that the power spike had caused the unit to turn on.

    I did manage to turn it off by unplugging the controller and that is how we are currently managing to keep the house cool, plug it in for cooling, unplug it to turn it off.

    I cannot see any visible signs of damage in the wall mount unit and I haven't been on the roof to check the controller, it's a bit warm for that at the moment.

    Got any suggestions for what to look for when I do get up there in the next day or so?

    Regards,
    Brent

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    Replies
    1. Hello Brent,

      If you did have a power spike/surge during that event then anything is possible and you won't necessarily have any visible damage.

      Even though it'd be rather coincidental, I suspect it might turn out to be caused by damage to your communications cable, the one that runs from the cooler to the wall control, as the issue you describe is often caused by that on the older models that used an analog communication interface. It can also be caused by the ground wire for the wall control going open-circuit somewhere.

      I'd suggest you check as much of the communication cable for damage as possible. The entire length should be checked, but I realise that isn't always easy. The main places to check are where the cable exits from the dropper (often a metal box beneath the cooler on older models) and any other parts of the cable that mice, rats, possums, etc. could chew on.

      I'd also suggest you turn off the mains power to the cooler first and unplug it in the roof, to reduce any chance of electric shock. Of particular concern here, is the evaporative coolers with metal droppers beneath them. It doesn't seem to be standard practice to earth the dropper box, even though it often has mains wiring running through it and into the cooler. If the mains wiring is damaged, you could have a live dropper as well. This is both a fire risk and electrocution risk. I've seen one small fire caused by this exact issue, the fire damaged the communication cable in this case and caused the unit to turn itself on at random times. Disconnecting the wall control would also make this cooler turn off, as it used an analog communication interface.

      Regards,
      Rob.

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    2. G'Day Rob,

      Thanks for the reply. I'll definitely check that out as the pattern seems to match.

      I don't know about a power source in the roof but I will check. I can unplug it at the unit on the roof as I have done that before.

      I was planning to check out the control unit in the on roof unit for signs of damage and I'll check the communications cable at the same time.

      Sounds like a lot of fun getting in the roof on a mid 30s day. That's why I let my Austel license lapse, oh well, if it saves me money I can do this.

      Regards,
      Brent

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    3. Hi Brent,

      There should be a power socket in the roof for the evap, just pull the power there to be safe. If you can't find it or can't be bothered finding it, then you can always turn off the power to the whole house while you investigate it.

      Enjoy crawling around in the hot roof space. I'm sure you'll love it.

      Regards,
      Rob,

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    4. G'Day Robert,

      Unfortunately I caused myself a fairly serious injury recently and, at this stage cannot check out your suggestions.

      If you are interested in the details I've recorded it all on the http://brentmilne.com blog.

      Once I'm back to being able to use two hands again I'll follow up and let you know the result. It'll be cooler in the roof then in any case.

      Regards,
      Brent

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    5. Hi Brent,

      Under the circumstances I think you can be forgiven. At least you'll still have 5 fingers on that hand once everything has healed.

      Admittedly, when I was beginning to read your comment I thought you might have fallen off the roof. Try not to do that.

      Regards,
      Rob.

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  19. Hi Rob,
    Thanks for a great blog. We have a Breezair EWC in Adelaide that's about 5'ish years old with a wired controller. 4 or 5 times this summer while the system is off, we have noticed that the water is running and draining out of the tank. We hear the water run in the pipes and flow out the gutter into the street. Does the drain valve stay open when the system is off? Could the inlet solenoid randomly open? Where would I get a replacement inlet solenoid valve?
    Thanks, Cyle

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    Replies
    1. Hi Cyle,

      It's normal for the cooler to drain after a while of no use. By default, this is 36 hours. When you use the cooler in cool mode, it will close the drain valve, fill with water and start pumping it over the pads to cool the air. When you turn off the cooler, it doesn't open the drain valve. It keeps the water in the cooler for 36 hours (default setting). If you haven't turned the cooler back on and used it in cool mode within 36 hours, it will drain the water. It can do this in the middle of the night or day and does not need to be "on" to do it.

      You can manually drain the water from the cooler by turning it off and then holding the up and down buttons for about 5 seconds. "dr" will flash on the display and the water should drain. It won't refill until you go to use the cooler in cool mode again.

      That said, if fresh water is running into the cooler and then being drained straight back out, you have a fault. It can be the dump valve failing to close, but you'd be more likely to notice this when the cooler is on and you'll probably get service code "2" flashing on the wall control if it remains open.

      The solenoid valve can also fail and not open or close when it should. Likewise, the drain valve may open and fresh water may flow through the solenoid valve and down the drain.

      The electronics that control the dump valve and solenoid valve inside the control module hardly ever fail, so it isn't likely to be a fault in the control module.

      Regarding parts, I won't recommend any suppliers on the blog.

      Regards,
      Rob.

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  20. Hi Rob

    You helped me out a while back when I was having water inlet problems with the Coolair CPL. We replaced the solenoid with one purchased on ebay and it has been sweet since then.

    Another issue emerged the other day with the controller displaying the 04 fault code. However the unit seems to be functioning fine. Are there any symptoms I should be looking out for?

    At the beginning of your blog it says 04 means a problem with the unit dumping water. I don't think the outlet pipe is blocked so I presume it is the dump valve. If I was in Melbourne I'd gladly get you to fix the problem as I haven't had much luck with air con people here in Perth. Are the valves reasonably priced and simple to replace?

    Thanks

    Frank

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  21. Hi Rob

    Just wanted to add to that 04 fault issue. We haven't used the air con for a while as the summer is pretty much over. I turned on the unit again, it operated as normal ie a couple minutes of waiting until water fills the tank. I then tried the drain function (ie pressing both up and down buttons together) and it drained as it should. It seems to me that there is no draining problem despite the 04 code. Given that the 04 code is not always displayed, could it be a random draining issue or something else all together?

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    Replies
    1. Hi Frank,

      The dump valve may be intermittently faulty, probably best to wait until it gets worse to get a better diagnosis.

      You'll basically have to catch it misbehaving. If the drain isn't blocked anywhere, then the next most likely thing is the dump/drain valve, followed by a problem with the control module (rare in this case). You can also try cleaning up the salinity probes if they're dirty, as they're used to determine if there is still water in the cooler when there shouldn't be.

      The water needs to drain (be below the sensing terminals/electrodes on the salinity probes) within 4 minutes of the cooler attempting to drain.

      Dump/drain valves are not cheap, they generally cost between $220.00 and about $300.00, so you'll want to make sure the diagnosis is correct before you buy one.

      Regards,
      Rob.

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  22. Thanks Rob, we'll keep it going.

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