Community Forums

Bald Eagle · 02-07-2009, 02:41 PM

I just read Darryl's post about an odor in the hot water. It reminded me that I need suggestions on my odor problem.

Class A motor home
Bathroom sink only

Our water smells fresh and clean but the odor seems to be coming from the sink drain. The odor is like stale water. Something like the odor inside a drain pipe. Definitely not the stink that the gray water tank is capable of.

I have removed all of the drain piping from the sink to the vertical riser that goes directly into the gray tank. It was relatively clean with the typical amount of residue. I cleaned everything well are reassembled the drain line.

My drain line vacuum breaker is only 6 months old and seems to be shutting off OK.

The odor is still present. It only smells when there is water flowing into the sink.

Could it be a bacteria growth inside the overflow canal inside the sink bowl? I don't know of a good way to clean out this little tunnel.

Any advice or suggestions? Thanks.

RV Wizard · 02-07-2009, 11:55 PM

Anything is possible and you could be right. To clean out the overflow you will need to block the drain below the bottom of the bowl. A simple drain plug in the bowl will not work. You may have to remove the "P" trap and plug it. Also plug the bottom of the bowl. Once you have this accomplished prepare a 50/50 mix of bleach and water and squirt it down into the over flow with something like a turkey baster till full. Let it stand for an hour or so.
Now the tricky part; get a large enough pan to catch this water and not get in on much as this could bleach fabrics and finishes.
Re-plumb the sink and flush the overflow with clean water well. Good luck and let us know how it turns out.

Fred and Bonnie · 02-08-2009, 10:22 AM

Gray tank odors can stink almost like black tanks. I use Odorlos chemical in the black tank and the gray tank alike. Solved the problem.

Fred

Fred Cooper · 02-08-2009, 05:30 PM

I'd bet that it is the vacuum break. Cheap enough to replace or install a spare to see if that cures the problem. I had one fail on the bath sink, and the smell was bad.....Fred

bldrbob · 02-09-2009, 04:15 PM

I put a plastic bag over the vacuum break with an elastic band to rule out a faulty valve.I had a problem with water leaking down around the toilet base and collecting on top of the tank.The odor would then come out under the sink .
BOB

Bald Eagle · 02-22-2009, 08:57 AM

Here's a follow-up on what I did to eliminate my sink odor problem.

First I removed all doubt that it was not my vacuum breaker valve under the sink. I have never had any odor under the sink. I'm sure if the vacuum breaker was stuck open I would have smelled something under there. I used Saran Wrap and rubber bands to seal the vacuum breaker for several days. The odor was still there. I knew all along that this odor was not the gray tank smell.

I removed the drain trap under the sink.

I used Saran Wrap and rubber bands to seal the sink drain. I also always use a dishpan under my working area in there to reduce the mess if I have an accident.

I used RV Wizard's suggestion and used my battery water syringe to inject full strength Clorox into the little overflow opening in the sink until full.

I let the chlorine do it's thing all night.

The next morning I used an ice pick to poke a tiny hole in the stretch wrap material to allow a controlled flow drainage of the Clorox into the dishpan. I used the syringe to flush the overflow passage with clean water.

After disposing of the Clorox water I put everything back together.

It has been almost two weeks and no old dirty water smell anymore.

Horay!

RV Wizard · 02-22-2009, 11:20 PM

Glad to hear that you have resolved the mystery!

Doggy Daddy · 02-27-2009, 02:03 AM

Many tend to forget that if they do not use their shower or sinks for some time, the water in the pee trap evaporates and allows gasses to escape into the interior of the coach. So, ever so often, pour water into the sink and shower traps.

RV Wizard · 02-28-2009, 01:18 AM

We have found that even living full time in the coach that when traveling we can loose the water in the "P" traps and get an odor entering the coach. Now the wife doesn't even have to be told what to do. She just gets up and runs water down the shower and sinks and in a couple miles the odor is gone.

exrench · 02-28-2009, 05:27 PM

Be aware that you can get,in addition to bad smells,MOSQUITOS coming up through a dry P trap and invading your MH.I had a resident mosquito population in my grey water tank that I discovered after being bitten every time I visited the bathroom.Seems our washer/dryer P trap was dry after using it on an irregular basis during a period of hot weather.