The jury is out on how effective the UV systems can be at resolving air problems. (They were originally designed to prevent microbial growth on the HVAC equipment, not specifically the air passing through the ducts.)

The only effective way to control odors is to determine and resolve the source. Can you describe the smell and if it is constant, or comes and goes ?

Husband does not smell anything. But to me right now it smells like maybe a wood smell. Like someone's woodshop, but not as strong. I am sensitive and bothered by wood being cut. It gives me a horrible headache, burns my lungs, and I can't think of words I'm wanting to say. Having someone come and do a strong ozone treatment to see if that helps. Have had numerous things done to try to fix the problem. The smell (again husband smells nothing) changes. At one time it was like a dirty crawl space or maybe a dirty laundry room. At first it was a strong saw dust smell because they had to fix the decking on our roof and it got sucked into our electronic air cleaner. But nobody saw any holes. So they replaced the return ductwork, the plenum and a little beyond, cleaned the coil, cleaned all the ductwork and applied a microbial agent. It was so I could be in the house if I used Vick's Vapor Rub on my nose, but now it is so bad that doesn't do any good. I have had to leave the house. Any suggestions are greatly appreciated. A/C guys are of differing opinions and one wanted to a stick UV light (he thought it was dirty sock syndrome) and another not sure what you call that UV light but it cleans the air as the air passes it. I can't be around ozone, though, due to lung issues and ozone irritates lungs. I'm wondering if attic air is being sucked into the ductwork. They said that is not possible and no holes were found. (Of course, I don't know how they see anything because of all the insulation up there.) At a loss and drawing at straws for an answer. One guy thought it was the mastic they used or paint. I thought maybe it was the wood they used to change the platform the furnace sits on. But this was in Nov. and you would think things would be done off gassing. Help!

UV lights don't do anything to the air. The air moves way too fast, which means it isn't exposed to the UV long enough to get sterilized. They can be used if your coils are wet all the time because of a humid condition. The UV will also cause unnecessary breakdown of lots of parts.

You can read more here: http://highperformanceheatingandairconditioning.com/hvac-101/the-right-way-to-install/#purifiers

"I'm wondering if attic air is being sucked into the ductwork. They said that is not possible and no holes were found. "

this is where I'd start also.

invest in a duct test.

common leakage areas (from my 20 years of diagnostic testing) are:

supply and return plenum connections to equipment.

return plenum framing if ceiling return interior chase if wall return.

chase can also leak at cut in wall for return air grill. often walls are

left open at top of the return.

supply plenum:

holes are cut for ducts to be installed. these cuts have to be

mastic sealed, not duct tape, not foil tape, but a mastic tape

or paint on mastic. seal around this start collar must be continuous.

not just 3/4 of the circumference of the start collar.

supply boxes have openings on each corner. mastic seal.

where supply boxes penetrate the ceiling into the living space

is another hidden leakage site.

by removing the supply grill and using a mastic tape, these

leakage sites can be sealed from inside the house.

there is no fast easy way to seal duct leakage.

one takes a bucket of mastic and a roll of mastic tape,

and sits down and completely seals each duct.

hard to find folks who will take the time to do this.

a well sealed duct system has no need for uv lights.

which imho are a waste of money for the homeowner,

and a bandaid used by the hvac industry for duct systems

that are not sealed.

if nothing gets in or out of duct system...which is supposed

to be an air tight recirculation system...there is nothing to

be "cleaned" by uv light.

best of luck.

energy_rater-la,

Who do you get to do leak testing? I have had two heating/cooling companies out and told them that is what I thought was happening and both companies had someone go up in the attic and they didn't see anything. But who actually tests for leaks? Apparently, they don't.

tknx,

What does one do to solve the problem? A/C guys are all for UV lights (either stick or in the air stream). But if UV lights degrade the flex duct, wiring, and drain pan what does one use to solve the allergic reaction I'm having to the air? Suggestions more than welcome.

I mean there is a lot it could be including contamination or pulling air from undesirable places.

You really need someone who is an expert HVAC person, not just a random person - but I am having enough trouble finding one of my own to give you any hardcore advice.

I'd suggest maybe posting on hvac-talk.com. Lots of contractors hang out there. They also have a contractor map, so you can see if someone close to you is on there, see whether their posts look like they are hardcore, and give them a call.

The best place to start is a home inspector that also does home diagnostics. Which metro area is closest to you and I can send a link to the local ASHI chapter, where you'll be able to find more experienced inspectors .

It is interesting that you say you smell wood. Sometimes there are posts on this forum where the stud bay is used as a supply or return for the HVAC system. That scenario would expose the wood framing to the air flow. You should investigate to see if that exists in your house.

TrustPointInspections,

Orlando would be the closest.

To me, and I am not an HVAC expert, UV is putting a bandaid on whatever the problem is.

you don't "see" duct leakage. you test for it.

hvac companies test duct work. it is code even here in Louisiana, where

codes are only in the past few years including duct testing.

but you have to ask yourself if you trust them to test their own

work...or their buddy's work.

most common duct test is with a duct blaster, but flow hoods and

even blower doors can test duct leakage.

the duct blaster & blower door both exaggerate the leakage sites.

I bring homeowner or hvac tech into attic with my blower door

running to let them feel the leakage sites that I listed in my

post above. once they feel the leakage...you can't argue with that.

I mark leakage sites with blue tape.

folks like me, independent energy raters certified by nationwide

RESNET or energy auditors certified by BPI are other sources

of duct/house/diagnostic testing.

best of luck.

Mike, even ceiling returns have wood framing on the attic side

for returns. if the 2x framing isn't caulked to each 2x, the attic floor

and in corners of 2x framing you will get sawdust & wood smell.

Personally I like to seal the ceiling returns from inside the r/a

and then also from the attic side. just fyi from someone who

tests a lot of houses & duct systems.

Here is a link to find ASHI certified inspectors. Give them a call and let them know you need someone to help do some home troubleshooting.

TrustPoint Inspections and others.....wood smell gone.....now have paint-like smell. HVAC people bypassed (and possibly removed) the wood in the frame that the furnace was sitting on. Return now goes into a thick filter and into the furnace instead of into the box the furnace sat on which contained the wood causing the problem. But now I have a paint-like smell. They painted the trim in the garage around the unit, but my garage does NOT smell like paint and it has been several weeks. They pulled the furnace out and rerouted the return air into it and also added the April Aire filter. Thinking maybe it is mastic or some type of caulk or maybe something on the April Aire filter. Your thoughts? And if it is mastic or caulk....I know it should dry in no time....but I am sensitive to things other people don't notice.....if it is one of those things, how can I hurry up the curing process. I wasn't there when they did the work, so I don't know what all they did. I do know prior to this one of the workers put mastic on the inside of the return ductwork to make sure it was sealed good (maybe they did it again.) Any suggestions are greatly appreciated.

Assuming that the UV lamps actually do something for you, you could run them when away from the home if that time is significant, and shut them off when you are in the house. Ozone has a very short half life if there are surfaces that it can react with and there are always those surfaces for it to react with at altitudes that are occupied by humans. Don't take this as any suggestion that UV lamps, as they are typically installed, are useful for treating flowing air in ducts. I've never seen any evidence that indicates that they are. That does not mean that they won't help in your special case since no one seems to know what is going on..

I have a simular issue but just had uv turned off think it was contributing to the problem.