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Discussion Starter · #1 ·
I have a 10-year old Lifebreath 200 Max HRV. It stopped completely a few months ago, and my local repair guy and I are at our wits' end trying to make it run again. (I live in a rural area so help is hard to find.)

The fan spins freely by hand and starts up fine when we hot-wire it directly to power. We also replaced the control switch and circuit board (part no. 99-275) (Sorry but I can't post a link yet.)

...but when we turn it on, the red light flashes rapidly and the fan does not run. The damper motor closes as it should but that's the only sign of life. The manual says the rapid red light indicates defrost... but I can't see why. We are at a loss as to what is stopping the motor from spinning up. Could it possibly be a bad temperature sensor? Would that totally stop it from running?

Appreciate any suggestions!
 

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I have a 15 yr old 155 MAX and when you unplug it and then plug it back in it should do a self check of the circuit board and damper.

Try leave the timer switches if you have them to OFF. Put the main control switch above the house humidity level so it does not run and try de-humidify.

Then unplug it and plug it in.

It should cycle the fan thru the different speeds to check them and then open and close the defrost bypass damper.

The only time it goes into defrost is when the thermistor ( temp sensor ) which is in the intake pipe near the core gets below - 13C/8 F or somewhere in that area. The colder it gets the more often it defrosts.

I am not sure of the exact details of a 200 Max or newer unit than mine but they very rarely change them. Lifebreath likes to stay with their tried tested and true systems. Except for some problems with some ECM fan units they are very reliable.

If you have one of them or a more complex unit then I don't know what is happening.

Point is it should do a self check startup routine when plugged in or after a power failure. If not then the board may be bad. You may have a faulty thermistor or wiring to or from it to the board.

Try remove and reconnect all the wiring as you may have a poor connection at the board.

You could also try email Lifebreath and see if they have troubleshooting info and can help you.
 

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Discussion Starter · #3 ·
Thanks for the reply - when I plug in the unit, instead of cycling through the 5 fan speeds (as I recall it doing when it was working) it simply flashes green for a moment then rapid red. During this time the damper closes but the fan doesn't budge. I suspected a faulty board or bad connection, so I replaced the entire circuit board and controller but it didn't help. There is no remote control panel elsewhere in the house for this unit.

Do you think a faulty temp sensor could shut it down completely like this? I'm totally at a loss because the whole electronic control mechanism has been replaced without fixing a thing.
 

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I have never had a problem with a Lifebreath unit other than one noisy motor and I have seen thousands of them. Very popular where I am.

The thermistor/defrost sensor could be shorted and maybe the board thinks it needs to go to defrost immediately.

Usually at normal plugged in startup it runs the fan for 30 seconds and checks the temp and then starts defrost if necessary.

One mine it is at the inlet where the cold air enters the unit and coil. 1" long black plastic wire thingy with a slight bulbed end.
 

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Discussion Starter · #5 ·
Appreciate the comments! So, if my thermistor/defrost sensor is shorted, and it went into defrost mode, wouldn't the fan still start spinning? Or is defrost mode a silent, "sit and wait" mode?

If defrost mode = sit and wait to warm up, then maybe that's what's happening to me. I have been assuming defrost mode would involve fan action as well?
 

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I have an older 155 like Yuri so things may be different. You could try to remove the leads from the humidistat and possibly short them and see what changes. With our older model, the fan is always on (unless, of course, set to 'off'). The humidistat opens the damper - it may possibly increase the fan speed, I haven't checked it that closely.
 

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Appreciate the comments! So, if my thermistor/defrost sensor is shorted, and it went into defrost mode, wouldn't the fan still start spinning? Or is defrost mode a silent, "sit and wait" mode?

If defrost mode = sit and wait to warm up, then maybe that's what's happening to me. I have been assuming defrost mode would involve fan action as well?
Normally the unit sits idle until the de-humidistat turns it on or a timer switch in a bathroom. Then it starts and runs the fan for 30 seconds while checking the thermistor temp to see if the coil is frozen or to run a defrost cycle based on outdoor temp.

The fan should run B4 it goes into defrost. I am guessing as to what could be wrong and have had very very few problems with them. They make them for Lennox and stamp Lennox on them and paint them brown.
 
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