Sewage smell in coach

January 22, 2011, 11:52:44 am

This is a repost of message #34350 dated 09/22/2007:

I haven't been following this discussion much, but want to share my "smelly" experience with my new 2007 Allure last year.

We had a smell in our pantry cabinet that would be especially noticeable when there was a negative pressure in the coach (i.e., exhaust fans running with windows closed).

Searched and searched. Caulked some small holes through the floor below the cabinet. Not luck. Did the Dakar test. Dripped some aftershave down the roof vent. Really thought there was a bad ABS pipe crack or joint as I could smell it in the pantry behind the electrical panel.

Bottom line. CC sawed off the vent pipes too short. Yes they went through the larger holes in the roof, but not far enough to go through the flange seals on the roof vents. With the vent cap removed, the pipe should extend THROUGH the seal of the roof vent.
It did not.

It is amazing how much smell can be sucked back through the 2" hole that the 1.5 inch vent pipe goes through, if the part of the vent cap that attaches to the roof does not slide over the vent pipe to form a tight seal!!!!

In this situation, it is conceivable that if water got under the vent cap (driving rain), or a backed up line (backwashing with the drain closed and the tank overfilles, water (clearn or dirty) would flow back into the coach through thw 2" roof hole that the 1.5" vent pipe extends through.

CC removed all vent caps. We could see which pipes were not long enoughm. For those, we removed the vent flanges, added a lot of putty and sealant, replaced the flange and caps. NO MORE SMELL in the coach, and no danger of a driving rain leaking into the coach.
All but one of the roof vents had pipes which were too short and did not properly seal.

You see, they install the vents pipes, cut them off, install the roof, and don't discover that the vent pipes are one inch too short to properly seal.
Herb

2007 Allure #31466

Re: Sewage smell in coach

Reply #1 – January 22, 2011, 12:06:20 pm

Yahoo Message Number: 67697

Excellent information Herb. Think mine maybe the same, i.e. to short. Installed the venture wind vane tops and noticed they did help reduce the order. Do not remember if I sealed around the pipes. Remember I had to add to one pipe to get the clearance between the vents so they could freely rotate. They do make a connector one could add to the pipes and make them longer to get above the roof.

Leonard 97' Magna 5418

Re: Sewage smell in coach

Reply #2 – January 23, 2011, 01:03:24 pm

Yahoo Message Number: 67722

Herb, good to hear from you.

I wish you were commenting on a more pleasant subject then tank odors.
Anyway, we appreciate all you do for this forum and by the comments posted many CC owners depend on the information.
We always have an answer and on certain rare occasions we do get it right.
Best regards
AL

00 affinity #5851

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