Stink!

I had the opposite situation. My trailer smelled exactly like propane a couple weeks ago, but only when I flushed the toilet. First trip out and trailer was sitting for six months. Dumped and gave the tank a good rinse, and it was gone. Never had that smell from my black tank before.

Whoops, that could have been bad. :) Glad you found it.

Lol glad I didn’t light a candle to cover the stink. It was a propane leak going from propane line to regulator. I resealed connection and all is well. Bet I got a **** clean gray tank too.

opnspaces wrote:
The valve is in the cabinet under the sink. Trace the drain pipe and you will see the valve on a short vertical stub just after the P trap. You can just unscrew the valve and replace it with one from Home depot or Lowes.

This is a one way valve that will allow air into the drain pipe, but block air and therefore odors from coming back up the pipe and into the RV. By allowing air into the drain system just after the P trap it breaks any siphon effect from the draining of the sink. Without the valve the standing water in the P trap could get siphoned out and allow odors to come back up through the drain.

For what it's worth your stick and brick house also has a feature to break the drain siphon and prevent draining of the P trap. But on a house there is no valve, just a pipe sticking up through the roof. Since we don't need additional holes in our RV roof we use the valve.

Thank you!

The sink p-traps on a travel trailer can get pretty funky smelling. You might put a teaspoon of bleach in 4 - 6 oz of water in a measuring cup and slowly pour it down the drain and let it sit for a while. When conserving water the P-trap doesn't get flushed out as well as it does on a sink in the house. Then again P traps and houses can start to stink a bit from time to time.

They do make deodorizing tablets or pellets the size of marbles you can drop down the drain, let them dissolve and sit for a while. There are also deodorizing sticks that you can drop in the drain that don't flush through and dissolve slowly over days this will keep the drain smelling fresh for longer periods of time.

stew47 wrote:
Flushed tanks pretty well. Still stinks. Doesn’t stink under the sink so the new valve is working. Wondering if it isn’t something from the trap to drain.

Check the trap under the shower or tub. Usually there's an access panel you remove to take the trap off. We had that problem once, ie, gunked up trap.

Also it will either have a vent pipe to the roof or one of those cheater vents you just replaced

Flushed tanks pretty well. Still stinks. Doesn’t stink under the sink so the new valve is working. Wondering if it isn’t something from the trap to drain.

The valve is in the cabinet under the sink. Trace the drain pipe and you will see the valve on a short vertical stub just after the P trap. You can just unscrew the valve and replace it with one from Home depot or Lowes.

This is a one way valve that will allow air into the drain pipe, but block air and therefore odors from coming back up the pipe and into the RV. By allowing air into the drain system just after the P trap it breaks any siphon effect from the draining of the sink. Without the valve the standing water in the P trap could get siphoned out and allow odors to come back up through the drain.

For what it's worth your stick and brick house also has a feature to break the drain siphon and prevent draining of the P trap. But on a house there is no valve, just a pipe sticking up through the roof. Since we don't need additional holes in our RV roof we use the valve.

Ron3rd wrote:

jdc1 wrote:

stew47 wrote:
I pulled a drawer out and saw it but I couldn’t remember what they were called

In the construction trade we call them "Studor vents". If that's not the problem, check up on the roof for a missing vent cap and a nest built in the vent pipe

And make sure you get the Studor brand with stainless steel internals. It will be white. The cheap black plastic ones like shown have a cheap rubber flapper valve but that's what all the rigs come with.

I'm no stranger to trailer maintenance, but I am a neophyte when it comes to plumbing. Where is this valve located and exactly what does it do. I'm suspecting, from what I've read here, that it may be the source of an odor we're getting in our trailer on these hot days. The tanks have been dumped and I have RV Digest It in both tanks but still get a slight whiff of an odor on the really warm 90 degree days. I wasn't even aware of this valve.

I went to Lowe’s and they didn’t have studor brand. So I bought the cheap one and put it in last night. Still stinks. I’ll check the roof. Gonna go flush tank today too.