Forum Discussion
Old-Biscuit
Sep 01, 2016Explorer III
Are you SURE it is black tank odor and NOT grey tank odor??
Inside bathroom cabinet on sink drain line should be an 'Air Admittance Valve' that is hand screwed into a stub pipe just after 'P' Trap.
It allows air in when draining grey tank so negative pressure doesn't suck 'P' Trap dry
If it fails to close grey tank odors can come inside RV.....grey tank can stink as much as black tank
Just something else to check ........
Toilet floor flange is a rubber/foam gasket
Toilet should be tight (no wobble) to floor---just like at home
Inside bathroom cabinet on sink drain line should be an 'Air Admittance Valve' that is hand screwed into a stub pipe just after 'P' Trap.
It allows air in when draining grey tank so negative pressure doesn't suck 'P' Trap dry
If it fails to close grey tank odors can come inside RV.....grey tank can stink as much as black tank
Just something else to check ........
Toilet floor flange is a rubber/foam gasket
Toilet should be tight (no wobble) to floor---just like at home
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