Sewer smell

I have a 2002 Adventurer 32V that had the same problem when I bought it last year and my solution was to change both AAVs. It seems that most makers use $0.99 AAVs and they do leak/fail. I went to Lowes and bought two more reliable valves and installed them and WaLa no more smell. They were not inexpensive but IIRC they were about $10.00 each.

That would be my first "To Do" thing before even crawling up on the roof to check the vent pipes. It's worth it to be secure in knowing the better valves have little chance of failing.

If it's not your vent pipes and your black and grey tanks are clean, then another obscure cause of odor may be the water heater. I tracked sewer odor for several months to no avail, and thought I might have a propane leak, only to find that if I didn't drain and flush the water heater frequently, it smelled like the proverbial rotten egg. Now, I make sure to drain the water heater after each trip. No more smell.

I also thoroughly drain, and flush the black and grey tanks each time when I get back from a trip too. It's just part of the routine of unpacking. And I know some will say it's overkill, but at the end of the flushing, I put in 2 gallons of hot water with Dawn and Calgon to sit in there until my next trip. At the beginning of each trip, I also put in one bottle of the Camco blue or green treatment. Haven't had any smell in quite a while now.

Just my $0.02 worth......

If you have washer/dryer connections check the connections and vents in that area.

First question I'll ask is, does the toilet hold water? If it doesn't the seals are probably bad. We have the ball type toilet and had a real bad odor coming up through the dry seals. You can order new ball and seals and replace them yourself.

Sewer smells inside rv

Air Admittance Valves...under kitchen and bathroom sinks
'P' Traps not holding water...kitchen/bath sinks, shower and washing machine
Toilet floor flange gasket
Toilet bowl seal
Waste tank Vents


Check the above items
IF they are all functioning then you may have an issue with cracked line or bad seal at tanks where drain lines connect.

Air Admittance Valves are #1 suspect.......cheap rubber flapper held in place by rubber tang that gets stretched and doesn't pull flapper back up tight allowing grey tank STINK to come inside RV
Low end...cost $5/$6
Better quality ones available but higher price

Both tanks should have a vent out the roof. Check that it is in place and open.

There is also an air admittance valve under both sinks. If they are not working correctly they will let in a lot of stink.

Check the above and then give both tanks a total flush by filling full with clean water multiple times.

I would make sure the vents are connected. Can you tell if it is black or grey?
The grey water system quite often has under sink vent system. The vent there could be stuck open allowing odors to exhaust under the sinks. Would look something like this vent

Ck to see if the vent pipe is clear bugs build nests in the pipe just below the cover.