Sulfur Smell coming through Vents

[Krogers]

We notice a sulfur/sewage smell coming throughout our homes vents whenever we run upstairs sinks or toilets or the blower fan comes on. After which, we smell almost a musty smell.

It typically will only happen in the winter (as soon as we turn the A/C off)

Placing water into the drain in our Utility Closet doesn't seem to always work..in fact, we got in the habit of doing it everyday, and it seemed to have made things worse.

We at times will also smell it coming through our sinks--running water down the drain seems to help this problem.

We aren't sure if it is a plumbing problem or a HVAC problem. The only thing we know is that we want a long term solution to eliminate this odor. As you can imagine, when we have guests and it all of a sudden decides to present itself...it isn't pleasant. Also replicating the smell for a technician is proving to be difficult.

We live in a 3 story townhouse on a slab foundation in Northern Virginia. Built in early 2000's. Our utility closet is on the bottom level with a sealed door opening to the garage. It is vented with two vents into our basement bottom level. AT times, we can smell the smell coming from the closet through these vents (and if we go in the closet) Some of our other neighbors with different models have the same problem.

Any and all help would be appreciated!

[HayZee518]

first thing to check is that the stack vent is clear from the first floor cleanout all the way to the roof pipe. sewer gases rises just like smoke in a chimney. the individual traps at your lavatory sink, kitchen sink, shower/tub are protected by their own trap. there should be water in all of them. the water layer is what keeps the sewer gases where they belong - out of the house! if there is a clog at some intermediate point the gases could be bubbling back through the trap water and out of your sink into the room. next person that uses the sink adds water to the drain to reseal the gases until the next person flushes or drains the line above the floor above.

[Gary Slusser]

Sanitize the traps, use a cap full of bleach in some water and pour it down each sink. Let it sit 20-30 minutes and rinse it down.

You may want to get some chlorinated water down each sink overflow also.

You could also sanitize each faucet aerator with a bit of bleach in a glass of water and remove the faucet tip and put it in the glass for 20-30 minutes.

Have you made sure the odor isn't in your water? The best way to tell is to use a bucket and run a strong flow into the bucket as you hang your nose, or hers, on the rim of the bucket smelling deeply for the odor. The tub or a utility sink is the best place to sample from.

[Krogers]

thanks to all for your help.
We pulled the anode rod out a few years ago--and that helped the smell in our water.

We will definitely do the bleach and trap trick (as we have never done that anyhow)

But checking the vent pipe out of our roof..would that be a white PVC looking pipe or the silver "smokestack" looking pipe? We have "heard" that some of our neighbors have been told by the same plumber that they don't have a sewage vent pipe---is that even possible?

We have both the white and the silver vent coming out..and I assume the vent is one of those? However, we do get a lot of leaves on the top of our house so it wouldn't surprise me if it is clogged.

Would that be a plumber or a HVAC issue? Who do we need to call at this point?

Thanks again, guys. Great forum.

[pushkins]

I had the 'smelly water" problem (hot) a while back and it really only seemed to start after I fitted a whole house filter, now I cannot say that the filter was "a" cause or "the" cause but around the same time I reduced the hot water tank temp. settings to 120F. I tried flushing the system with chlorine to remove the bacteria and it worked for a time then the smell slowly returned, I contacted the manufacturer of the h2o tank and they recommended I buy and install a special anode in the tank, before I bought the anode i did a little more digging and found that the particular bacteria that produce the sulfur smell (harmless to humans) bloom in hot water under 130F. I raised the h2o temp to over 130 (somewhere around 140F) and the problem was solved and hasn't returned.

University studies have shown that the combination of significantly reduced chlorine levels by some whole house water filters and the recommendation from government departments to reduce h2o tanks to the minimum settings (120F) are major contributing factors to these non harmful bacteria blooms

Just a little piece of information that might be handy to know.