OK folks, here is a puzzle. We have developed a bad sewer smell, but only in the cabinet under the island Peninsula in our Elkridge QSRL. It's the cabinet to the right if you are standing at the sink for those of you familiar with out floor plan. There is a black pipe in the back corner of the cabinet and i think it is the sewer vent pipe. The black tank was flushed as we usually do. We've never had this issue. If the smell were in the bathroom too I might think it is the tank just not being clean, but it's under thus cabinet.... Any ideas??
Help!! New sewer smell... Yuck!!
- Thread starter Sunset4k
- Start date
Garypowell
Well-known member
More than likely you have a bad vent valve.....at least that is what most will say....and it might be true. I just replaced mine ($8 at Home Depot). But the smell did not diminish. Then I realized there were a couple of small leaks. One was right at the sink drain. The other was in one of the joints of the P trap piping where the sink comes into the P trap. So for $3.50 picked up a new P trap. Took the drain out of the sink and cleaned it thoroughly then used some pipe joint compound to seal around the flange before I put it back in (I know I should have used plumbers putty but did not want to spend the extra money and carry around what was left).
This stopped that weeping under the sink drain but found another one where the straight piece comes off the P trap....this is a pressure fit with no gasket. Realigned it and tightened everything down good. Smell is gone but had to wipe the area down after spraying a heavy dose of air freshener under there.
Oh, this was a bathroom sink.
Have the same thing going on under my Kitchen sink....I'll do that at the next stop in Charleston. Already changed out the vent....but as before with the bathroom the smell continues.
Good luck.
This stopped that weeping under the sink drain but found another one where the straight piece comes off the P trap....this is a pressure fit with no gasket. Realigned it and tightened everything down good. Smell is gone but had to wipe the area down after spraying a heavy dose of air freshener under there.
Oh, this was a bathroom sink.
Have the same thing going on under my Kitchen sink....I'll do that at the next stop in Charleston. Already changed out the vent....but as before with the bathroom the smell continues.
Good luck.
rxbristol
Well-known member
The vent tubes are probably not sealed at the roof opening which allow the gases to come back down into the ceiling and walls. Go on the roof, remove the vent cover screw, pop the vent cover top off and you'll find a gap between the vent pipe and roof. Seal this area. I used the expanding foam...very little is needed by the way, so be careful. This fixed my problem and a few others in this forum. All RV's seem to have this issue.
TravelTiger
Founding Texas-West Chapter Leaders-Retired
It could be the studor vent. Do a search on Google, there are some drawings of how this vent might be installed. Get a good flashlight and study the pipes from sink all the way down through the L peninsula. You might have a broken pipe somewhere. The grey tank is directly below the L peninsula, and the vent pipe runs up behind the cabinet against the wall at the termination of the L.
I have not smelled odors, but have found fittings lose under there before. I also use a grey tank additive occasionally to help with odors.
I have not smelled odors, but have found fittings lose under there before. I also use a grey tank additive occasionally to help with odors.
rxbristol
Well-known member
I've looked for a studor vent on my rig and do not see one under the sink. Is it located somewhere else?
TravelTiger
Founding Texas-West Chapter Leaders-Retired
Honestly, I can't say. I don't know if I've got one, but I do know the sink piping follows the L shaped peninsula, so it could be "around the bend"?
Chevyfan388
Member
rxbristol
Well-known member
It looks like they never continued the vent pipe through the roof.
Chevyfan388
Member
The vent pipe in the wall had a joint coupling that wasn't glued so the pipe was loose and actually was found next to the pipe it was supposed to be connected to. In other words it was venting into the wall behind the toilet and not out the roof....
Rex, thanks to you and this forum my deadly problem is solved. We have only had our Landmark 5 months, but we have noticed in the last two weeks or so deadly sewer gas fumes in the coach. After researching the forum I found your post and you were right on the mark, I found all three of my vent pipes cut way to short and large gaps around the pipe, every time the AC cut on we were being engulfed with sewer gas. This gas is sucked in through the AC plenum. I suppose the quality control at Landmark leaves something to be desired. I am sending pictures to Landmark right away in hopes they will correct this quality control problem quickly*************. Thanks, again, Trip
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