Can't get answer from Carrier - AC tech only gives me a ?. Had evaporator cleaned 3 months ago. About 1 month after that when AC on cool - there is a strong odor - like wet cardboard or musty smell. It only does it on COOL - on heat it is fine - no odor at all. I have asked Carrier and they refuse to answer and the AC tech that cleaned it says no - and they have checked air handler and can find nothing wrong - no mold-nothing. The evaporator was not cleaned for 10 years even though I paid a AC rip off company to service the unit every 6 months - when it plugged up I had water everywhere - wood wet, floor wet. I have painted all the wood and floor. HELP!