Paint Smell Coming From Furnace
Last fall I painted one room in a small apartment with oil based primer. When I bought the primer, the very experienced paint guy told me not to run the furnace because it would take a long time to get the oil primer smell out of the hvac system. By the time I got around to actualling putting the primer on the temperature outside had dropped into the low 30's and I was pretty much forced to run the furnace during the painting process and after. It is now at least 4 months later and I can still smell an odor coming from the ducts. There was no odor there prior to the painting so I am assuming paint is the cause. I have painted with latex while the furnace was runnining the past and not had an issue but this is my first time using an oil based primer indoors. If you just let the fan run there is no odor at all...it only happens when the burners are on. The odor can be smelled primarily after the heat exchanger.
Has anyone ever heard of this issue and any way to minimize the odor?
Thanks in advance for your replies.
Last edited by chevys10; 03-11-2009 at 03:18 PM.
Do you have a small portable electric space heater.
If so, turn the stat to off. And put the heater in that room. And set the temp up high.
If you start to get that odor in that room, then the primer is still curing/off gassing.
And you can't do much about it. Except repaint the room with an acrylic paint, to seal in the primer odor.
There are 2 coats of acrylic latex on top of the oil base primer. There is no odor at all in the room unless the furnace is firing.
Any chance primer got in the ducts or register boots while you were primering.
You may want to call a restoration company.
They know how to handle odors.
No primer directly entered the ductwork. The theory is that the fumes traveled throught the ducts and were "baked" onto the heat exchanger or surrounding hot duct work. I can't think of any other reason I would be getting that smell.
What did the paint guy say?
Originally Posted by chevys10
Sometimes it is good to listen to those "very experienced" tradesmen.
Psalm 51:10, 12
Change the filters?
"All paints release trace amounts of gases for months after application."
The paint manuf. may be able to help with this problem.
"Outgassing" can occure for extended periods until all solvents have evaporated. Elevating temps have a tendency to cause solvents to "boil" off but eventually this effect will subside. I do, however, find it hard to believe that an extended period of odor could result from the minimal deposits of paint product in the situation you described.
A good HVAC tech knows how, an educated HVAC tech knows why!
I have been running a charcoal impregnated filter for the past few weeks to try and remove some of the smell. The "very experienced" paint guy said I might have to clean the duct work but said that this might only help a bit. Actually, he is extremely knowledgable....in his 60's and been painting most of his life and now owns a paint store. I make a special trip across town to purchase from him.
One part that I left out is that I had the exact same situation in the downstairs apartment in the same room. Same amount of oil based primer with the same amount of latex top coat.....except I did not run the furnace for at least a month after the paint was dry. Separate furnace for each apartment and that one has absolutely no odor what so ever.
I suppose that the smell could be coming from something else but what?
It is a sweet smell, not like an electrical issue with the furnace itself. It is not musty at all.
I vaccumed out the burners quite well and there was a white powder on them....is that in any way related to this??
I'm wondering if a paint manuf. knows of a catalyst that will stop whatever process is causing this smell. Either stop it, or speed it up so much that the smell is gone within a few hours.
This catalyst would have to be airborne and you'd probably have leave the house for while.
You might also inquire on an Internet forum for chemists.
I have been researching cleaners/deodorizers for hvac systems and am wondering if i should try a no-rinse a-coil cleaner just to see if it helps any. It is probably a long shot, but a last resort before calling someone in to look at it. I have access to the coil via the old non-working humidifier so I might give it a shot.
If the A coil has a surface area of XX and the rest of the system including ducts has an interior surface area of YY, then XX/YY of the smell comes from the A coil, assuming the chemical that smells is uniformly distributed throughout the interior of your system.
Filters probably have more surface area than all of it put together. I'm wondering if new filters put into this system promptly become contaminated.