Hi all,

We started getting a burning smell from the vents. Indoor Unit is Daikin FDYQ160KAV1.

The motor still ran but there was little to no airflow from the vents - then after 20-30 minutes of operation, the smell would come through the vents... leave it overnight... turn it on again.. same thing, 20-30 minutes, burning smell....

I detached the fan deck and took it out of the roof, found the motor to be completely blackened / same smell came from the motor. There are no signs of failure of the run / start capacitor whatsoever.

I purchased a new fan motor (slightly bigger, 750w(?_, the one in there was 655). I replaced the capacitor as well just to be sure.

I turned it on and it was running very quiet - spinning very well. However there wasn't much of any airflow still - it was like the fan speed was turned right down. I tried changing the field setting (23) code 6 to its max value of 3 (odd, it only has 3 speed settings?). It made no difference at all.

Then low and behold after 30 minutes of being on cool mode, the same smell came back... The motor must be overheating for some reason or something else is causing it to burn out?

Does anyone know what this could possibly be?

I am reluctant to think that its the PCB, given everything else seems to operate fine - could it really be the PCB causing to much voltage to run through the motor and overheat it / burn it out? I cant think of any other component that is independent to the motor itself that would cause this?

The smell itself to be honest, sort of smells like refrigerant as well - I cant be 100% sure of this - but could the issue be at the compressor side, and leaking refrigerant gas into the fan assembly causing the motor to burn out? My thought on this theory is that the air is pushing out of the fan deck so even if this was the case, it should be pushing that gas away from the motor... so this theory is out....

I wanted to know if anyone thinks I should replace the PCB and what they think the chances of it being this would be? The green light on the PCB flashes - but I suspected this to be normal, but maybe its not? Maybe the reason why its running the fan so low is indicator of another issue? Is there any another way to reset the PCB somehow other than turning the isolator off? (Which I have done for > 24 hour periods with no effect).

Thanks,

Matt