AH coils

[S. Lamar]

I opened the service panels on two Lennox Air Handlers and the coils were black in color and had several had a soot like residue on them. The air handlers were located in a designated hall closet, one 4 ton and one 2 ton. I work in central Florida and suspect it may be from chinese drywall. Could there be another cause?

[gregp]

smokers or candles?

[S. Lamar]

Thank you for the reply gregp.

[Bill Lee]

If the residue is only on the copper, then I would say that it was a chemical reaction with sulfur/sulfides in the air. This material is somewhat shiny in appearance and will flake off the copper tubing. If the material is all over the fin-pack then it is probably air borne particles--soot or dirt.

[S. Lamar]

Both units were installed in 2006. The home is occupied by the original owner. The discoloration was only on the coils. There was heavy dust accumulation on the fins, but no evidence of smokers or candle smells.

Thank you Bill Lee.

[acmanko]

were they painted to help with keeping the salty air from corrodeing them?

[S. Lamar]

They did not appear to be painted. The home is located in Kissimmee, FL.

Thank you manko

[Bladeforger]

I've read a little about that Chinese drywall and talked to a friend of mine who helped demo some out of a commercial building. It's nasty stuff!! I wouldn't, personally, work around it if I knew what it was.

You can look here: http://en.wikipedia.org/wiki/2009_Ch...ivity_concerns

and you will find there, this text at the top:

The 2009 Chinese drywall controversy is a health and safety issue involving defective drywall manufactured in China and imported by the United States starting in 2001. Laboratory tests of samples for volatile chemicals have identified emissions of the sulfurous gases carbon disulfide, carbonyl sulfide, and hydrogen sulfide. These emissions, which have the odor of rotten eggs, worsen as temperature and humidity rise and cause copper surfaces to turn black and powdery, a chemical process indicative of reaction with hydrogen sulfide. Copper pipes, wiring, and air conditioner coils are affected, as well as silver jewelry. Homeowners have reported a variety of symptoms, including respiratory problems such as asthma attacks, chronic coughing and difficulty breathing, as well as chronic headaches and sinus issues.[1][2][3]

I'd say you ought to let the homeowner know about your suspicions and recommend that they contact their insurance company and/or a reputable testing company. Tell them to beware of scams.

Keith

[smooth_operator]

Is just might me mold...

[S. Lamar]

Thank you Bladeforger and smooth_operator for your responses.