Forum Discussion
wolfe10
Oct 18, 2015Explorer
Yes, the gray tank CAN smell almost as bad as the black.
If the smell is near a sink, assume there is water in the P trap.
If so, next suspect is the air admittance valve. Replacements from most box stores.
To test(while not using the sink): Put a zip lock bag over the air admittance valve, zip tie it tightly and see if the small is still there after a couple of hours. If that "cures" it, just replace it. The rubber diaphragms can dry out and leak that smell inside.
If the smell is near a sink, assume there is water in the P trap.
If so, next suspect is the air admittance valve. Replacements from most box stores.
To test(while not using the sink): Put a zip lock bag over the air admittance valve, zip tie it tightly and see if the small is still there after a couple of hours. If that "cures" it, just replace it. The rubber diaphragms can dry out and leak that smell inside.
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