White Powder residual from a Gas furnace???

[Greg Weatherford]

I have the same problem with my gas pack central unit, propane. I bought the unit new 3 yrs. ago. My old, original central unit was also propane. No problem. Same propane tank and supplier. The second year of using my current unit, we started noticing that everything was dusty. Looked like sheet rock dust. I've always kept my return air filters changed and used good filters. Last year I had to dust all the walls and doors. I've had my central unit checked by 2 different HVAC men and found no problem. I've stopped using the central heat and use my fireplace. Today, the white residue is above the firebox on the wood mantel. With my central unit, I've never had a problem with the air conditioner part. I need some advice.

[Jim Katen]

White propane residue should not be getting into the household air at all. If it is, that's a serious problem. 

You can have 10 HVAC men look at it and if they're crappy HVAC men they won't find anything. 

Find a good HVAC man and challenge him to chase down the problem until it's solved. 

[Mom]

My husband is a HVAC guy and the furnace was my son's... it turned out the white dust was being caused by a cracked heat exchanger. 

[CBrown]

I’ve used ventless over 30 years and this issue only developed when I switched from the radiant to the fake log heaters. Perhaps the fake logs are breaking down over a period of time. I’ve had this over 5 years now. I’m either going to vented or back to the radiant heaters before cold weather.