Sewer smell in cabin while driving

Ivylog wrote:
Replace the round roof vent caps with PVC Ts with the open ends facing front and back. Problem solved for less than $5.

X2

Thanks all!

We do run water in the sink, shower and toilet prior to leaving to seal them. We did replace the AVC thing under the kitchen sink and cleaned the roof vents and replaced one with a rotating vent. Our next trip is at the end of this month so we will test it out then!

We always run some water into our toilet after flushing to create a water barrier from the black water tank. There is no trap, it is a straight shot down.

Make sure you run water into all your sinks and shower to fill "p" traps or you can pull air through your gray water tank

on bigger rigs run cycle of washing machine or you will pull air through trap on washing machine and lots of oder.

My old class C would get that smell when driving it. I went up on the roof and checked the vent cap. I found the hole cut in the roof for the vent had about a 3/8 in. gap around the actual vent pipe. I sealed around the pipe, and the smell never came back.

I've not understood where these smells could be coming from, nor the need for fancy vents on the roof.

All pipes going into the waste tanks should be sealed from the cabin with water. All drains should have P traps that are full of water and thus prevent gasses from passing through, and the toilet should have a sealed valve that allows residual flush water to stand on top of it, also creating an air-tight seal.

So I'd make sure when you get on the road that all your drains have some water in them, and that the toilet has some water in the bowl. This is a good practice anyway as when you fill your water tanks your lines are full of air so you should run all your faucets when filling to make sure you get your tank full and all your lines full of water for maximum water carrying capability.

If you're getting stinks with all your drains full of water, you've got another problem. Somehow your waste tanks are venting into the cabin from somewhere else.

Steve

One extreme that would solve the problem for good would be to replace the traps under the sink and bathtub with HepVo waterless traps. These not just replace P traps, but they also replace air admittance valves.

Those will go a long way in ensuring the sewage smells from the black and gray tanks are long gone.

I also would consider a Camco cyclone vent cap or a Ultra-Fab mini plumbing vent (which uses a small solar panel and a fan.) Either of these will actively pull gases out. The Camco has better reviews, and is better if there is -any- wind at all, but the other brand will work if the sun is out.

Several possibilities.
AAV,air admittance valve, bad
sink or shower trap empty
seal between toilet and floor bad
seal IN toilet that you use to flush not holding water
seal around vent pipe to roof broken

And that is without thinking about it

Replace the round roof vent caps with PVC Ts with the open ends facing front and back. Problem solved for less than $5.

Or somebody is being the silent one and grinning like he!!