Stink!

Did you check for an air admittance valve under the kitchen sink?

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

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

You need to check the sink backflow valve, they can stick, cheap and easy to replace. Most any store has plumbing supplies.

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 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.

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.

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.

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.

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