Colder Outside Brings Smell Inside

HepaCore

Customer called describing a horrible smell once the temp drops. It permeates through the walls, through electric sockets and other openings. The HO lives in a Condo unit on top floor. The smell can even be detected outside and neighboring unit can smell it too. Filling the traps has no impact since they left a sink on a low flow over night (Don't they know there's a draught!)

Any ideas?

Putty Truck

The neighbor has a dead body in the trunk and when it's in the driveway, the smell wafts over.

The cold air is a given since it is fall and almost everyday is cold.

Herk

I'm not sure what the cold has to do with it, other than a difference in the direction that sewer gases move. If the gases in the sewer are warm, perhaps they rise better or something?

But I think I'd be checking the attic for a pipe thread that's broken from a fitting, or how close a plumbing vent is to an attic vent - whether on the roof or on the eave.

Although I'm no great fan of Studor vents, this might be one case where they work better than atmospheric. (And can someone explain to me why mechanical vents are illegal in a "house" but not illegal in a "manufactured house?" I'd think that once you put a factory-built house on a concrete foundation alongside its twins, the different regulations for "trailers" would disappear.)

The plumber

Smoke test the sewer lines. If there is a sewer gas leak that is the way to find it

RopeaGoat

Better than smoke... Do a peppermint test but don't let the guy pouring the peppermint into the unit until after you're done. That stuff is very potent. We used it on a new school and found the leak within 20 minutes.

Later...

BigJon3475

The amount of leakage is variable and depends on outside/inside temperature differential and the velocity of the wind. Most homes leak enough fresh air during the winter weather to approach the 200 cfm of fresh air and leak less in warmer weather. Is it possible this is something outside or in a crawl space and it's drawing into the condo since it's cooler outside?

The plumber

I found about 15 leaking wax rings in a school with a smoke test and I found them before the fire department showed up in under 10 minutes. I was not expecting that many leaks. Oops!!!