Strong urine smell coming from ducts

[2hot2coolme]

I don't think any type of sealant will do any good, that's the smelly problem, the fiberboard. I remember installing spacepack & unico systems with that fiberboard (round pipe) it was brand new and boyyy did it smell like piss! We were still told to install it. I'm sure glad they changed to rigid metal for the trunkline. Looks like you will have to replace that smelly ductwork.

[drk]

Coat it with a good coating and it will be fine

[2hot2coolme]

Originally posted by drk
Coat it with a good coating and it will be fine

Go back and re-read OP's update.

[Roscoe]

Damn Ferrets

Do you or did the previous owner have Ferrets

See condenseddave he is an expert on this subject


damn polecats, do a search on Ferrets

[supremehvac]

It sounds like the problem is in the duct going to the kicthen. Is this where the smell is still the strongest? If you get some cooler weather you should try shuting off the unit that supplies the upstairs and kicthen for a day or so and see if the smell goes away. Then run just the other unit and see if there is a noticeable difference. I would experiment like this and try to isolate the problem.

Duct cleaning is one of the biggest scams I have ever seen. Homeowners can't see inside their ducts and herein lies the problem. With such a great open market to scam there are hundreds of outfits that spring up. There are a handful that do it right and the odds that you have found one of them is slim. Don't get any more duct cleaning done, your just throwing money away. Your money would be better spent towards a contractor that specializes in IAQ and is willing to solve your problem.

How long did you live in the house before the units were changed out and did it smell then?

You said the smell was foul, then it got worse, and now it is less and has changed. This sounds like a decaying animal to me. I remember a job I went on years ago that was somewhat similar. It was a peace and police officers association building in the city. The secretary told me when I arrived they had a bad smell in the building for quite some time but lately it has been worse, especially when the A/C is running. I checked out the roof top unit in question and couldn't find the source, although a slight foul smell did linger. I started walking around the inside and determined the smell was worse in the conference room. I lifted up many ceiling tiles until I came across an area that was pretty foul. It was near a steel pole which supported a main support beam of the building, and it was cased in on all sides by sheet rock. There were many anti smell canisters placed around it but apparently no one else who had come out to investigate the smell took a peek down this incased area. I stuck my head over it and looked down and saw the biggest rat I have ever seen in my life. I had no idea they could get that big, it was dark because it was above the ceiling tiles but I could see the outline of the body and the rings on its long tail. And once I had my nose right over the thing it was the foulest thing I have ever smelt to this day, worse than changing a diaper. I have no idea how this rat of this size got in, but it must have been crawling around on top of the ceiling tiles, fell into the encloser, and couldn't crawl back up and died.

My point is that the smell may seem like it comes from the ducts, but it could be something dead and hidden else where. Even my big nose had trouble finding that dead rat, took the better part of the morning. The ozone machine is just a band aid you still need to find the source. Good luck in your search for the smell.

[lisag]

What happened?! This was like reading a mystery novel...I'm dying to know what the final outcome was!

[H&C Guy]

When you bought the house, did it smell when the system was running?

Fiberglass duct is made with a thermosetting resin(glue) that has urea as one component. When it is used in the correct amount, distributed evenly through the matrix of the board, and dried COMPLETELY, there is no problem. When it is used too heavy, concentrated in the matrix, and/or left too wet from the factory it smells like --- URINE (and several other unpleasant descriptions I have heard).

Another reason for fiberglass duct smelling may be that the system is introducing moisture from the cooling coil onto the surface of the duct. There are times when the air velocity through the cooling coil is too fast and condensation will blow off the coil, onto the duct surface, soaking the duct surface. Another one I ran into was a drain pan that was sloped away from the drain opening. The condensation that was supposed to be running out the drain couldn't and overflowed from the coil drain pan onto the duct surface. That house really smelled bad!

Solution if the duct board is wet, is to replace the duct. Don't let anyone tell you it can be dried successfully for the long term. If the condition were stopped very early in the beginning of the problem, this would have been possible. The drying process would have had to happened quickly. What has happened by now, is the conditions for mold and/or mildew growth have existed for too long, and it is time for the wet portions of the duct to go.

Do not apply top coating products that the manufacturer of the ductboard does not supply. These top-coatings/sealants may deterioriate the resins and cause lots bigger problems than you have now. To identify the manufacturer of the board, look on the outside of the duct. Every piece of board is made with this information on it.

[captainrat]

who pissed in the ducts ? have that crap replaced with metal.

[deerwhistle]

My neighbour once asked me to look at his hi-boy furnace because of a real strong urine smell coming out of it. Turns out his two little boys were using the control cabinet/burner deck as a latrine. Yes, the urine ruined the deck.

[arcticair]

im gonna go with rats if not look and see what the shape of your coil is if youve had your ducts cleaned recently call them back they should have cleaned the evaporater coil


i have seen where returns located near kitchen will get a good coating of grease through the system it smell like pee when it gets old

[arcticair]

it was me i like top pee on customers units this way i can get more work and the istant relief

[air2spare]

inspect the duct for damage by vermin. It is always pretty obvious where they chewed their way in and leave a traffic trail. If there are no openings, there are no vermin so look elsewhere. IMHO

[leadmech2006]

my first question is: Is your son peeing in the air duct? (I've seen this before) or how about a pet? (seen that too) Also any time you have mold resident in your furnace, coil or air handler it is in you whole system. The whole thing needs to be treated more than likely it would be better to replace the whol thing installing a air cleaner and a UV light installed below the coil.

[syntropicsystems]

Odors = volatile organic compounds or other chemicals that you are smelling. The source of the VOCs might be mold, urine, decaying organics (dead stuff), bacteria, or off gassing from the chemical compounds in building materials. UV lights don't do anything for VOCs and can create a potentially hazardous situation from breakage. Actually effectiveness on "killing" microbials such as mold and bacteria depends upon dwell time and intensity. Too much of the exposure to UV radiation can be bad for plastics. Carbon filtration may remove VOCs from the airstream but don't do anything to eliminate the root cause. Oxidation of compounds, whether they be VOCs or nanoparticles such as carbon black, based on University research results reduce the toxicity levels significantly. EPA findings on Advanced Photocatalytic Oxidation processes in their 1998 Handbook help to explain why Photocatalytic Oxidation reduced and virtually eliminated VOCs.

[cg2]

Ahhhh dont you love the smell of strong urine in the morning?

Why did this old thread get bumped again? I need to get off the mailing list for this one!

[ezhfjs]

I have lost track of this thread, but wow, thanks for all the input.

Embarrassingly this issue still has not been solved - partly because the uriney-damp smell comes and goes and partly because I am not sure what path to take to getting this solved. Given that the smell is bad again (the air conditioning is currently off) I really need to get this fixed!!

We had the house inspected multiple times for mold and vermin and even tented it so the smell is definitely is not peeing or rotting vermin. I've also made several calls to ask about having the air ducts sealed but as I am not even 100% certain this will solve the problem, I've been reluctant to throw more money at the problem...

H&C Guy mentioned damp fiberboard and I was thinking some more about this:

The foul smells come through the air duct in our downstairs kitchen. Due to some bizarre construction, the kitchen is the only downstairs room that is cooled by the upstairs ducting system. The upstairs duct travels via the master bath and twists its way downstairs to the kitchen. Currently the master bath does not have an extractor fan to remove moisture.

Could it be the case that the dampness from the bathroom gets caught in the twisting duct and causes the foul odor downstairs in the kitchen?

If this could be the cause of the problem - what do we do and who do I call to fix?

Thanks and I hope that my next posting is to tell you this has been solved

[tommy graham]

had this same problem with one of my customers rental houses, turned out it was the son weeweeing in the vents, check your vents(supply & returns) and see if they have rust on then, and will probally find you have the same situation. Funny thing about it was they moved out and the weewee smell moved out too





“Tell me and I forget. Teach me and I remember. Involve me and I learn.”

[auburnchris]

an old thread i know but a new idea..i dont think it was mentioned hps or furnaces but the smell could always be coming from a drain..if mains are dropped into a plumbing stack instead of outside and are not down into the water then with the negative pressure of a heat pump the smell could be sucking up through the drain pipe and into the unit..mold grows in the plumbing stacks as they dry out over the winter when no water is coming trough..if the drains are ran outside they could still have mold in them especially if there is any part that is level or ran up hill..surprised no one mentioned drains before..ive ran into several times and it smells pretty bad

[Nalalove10]

ezhfjs I realize it's been years since you posted about the smell coming from you air ducts, so you may never see this post. I have duct board in my air duct system and have recently had a mice infestation where the were living in my duct work. The smell is so bad I wanna move out! I am wondering what you did to solve your problem, besides have ducts cleaned. I have had my cleaned, but because of the fact that they are made of duct board the company was not able to use a rotary brush to scrape the duct work. Basically all they could do was suck out all the mice poop and other debris. Any input from anyone that can help is appreciated. It's a sad and bad situation! Thank You

[Nalalove10]

Captainrat

Not everyone can afford to replace their duct work. It costs thousands of dollars.