We are noticing a smell of sewer intermittently. we have thoroughly cleaned the black tank, including dumping 3 five gallon pails of water down the toilet. we also used 2 deodorizers. Help please
Grey can smell as bad as black. If your Air admittance valve is under the sink and has failed, that can easily be the culprit. Try covering it with a plastic bag and seal it to the pipe with a rubber band or tape. If the smell stops, you have your answer (dont leave it that way). The parts they use in RV's are pure junk - one of mine failed the first season. You can get a quality replacement at Lowes or Home depot.