I had the same issue. You can pour some water down the vent pipe to make sure there is water in the P trap to stop the smell from coming into the coach.
This worked for me.
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Thanks,
rkulbok
(Ron & Karin)
2015 Georgetown 328TS
Full time since October 2015
I had the same issue. You can pour some water down the vent pipe to make sure there is water in the P trap to stop the smell from coming into the coach.