will apologize in advance if I am violating any rules by being a non-pro who needs some help but my AC guy (whom I really like alot and respect) isnt coming up with any answers. Also I posted this in "general discussion" before seeing this board which seems more appropriate so I am double posting, so sorry for that too.
I have a 1 year Central AC and heat system with a gas heater and blower in the attic. Whenever I turn the heater on, it snows flat, dandruff-like flakes.
It only happens when the heater is turned on after the A/C has been running for a while. If the heater runs for a few days, it eventually clears up. But then if you turn the A/C on, it seems to reactivate the problem and the next time the heat is activated again, it snows again.
This logically would seem to me to be water related somehow. Like there is something the A/C water is wetting which prevents the snow, but once the heat is turned on, whatever it is dries out and begins flaking
My AC guy first told me it was the fact that my ceilings in this old house are layered sheet rock on top of plaster and thus the supply grilles arent getting a good seal and the dust Im seeing is either sheet rock or plaster. He sealed one of them with foam just to test but that did not solve it.
Also the doest really doesnt seem like either of those things as I would expect it to be either powdery or granular while these are very clearly flat flakes like dandruff.
I went up there myself to poke around. I pulled off a duct from the plenum and found the white flakes throughout the duct which I thought might disprove the supply-grill-bad-ceiling-seal theory.
I also noticed that the 1" PVC drain out of the A/C actually travels gradually up for about 2 feet before draining out of the house which I thught might somehow relate to my water-based theory.
Hes coming over for a third time next week. Any ideas I could suggest to him?