Forum Discussion

ajriding's avatar
ajriding
Explorer II
Feb 24, 2019

How big does the waste tank vent hole need to be?

I am repairing faulty repairs. My gray tank is fiberglass it looks like. The vent broke right at the top of the tank. To complicate it, in order to re-install tank it needs to slide, so I cannot h...
time2roll's avatar
time2roll
Nomad
Feb 25, 2019
Yes and I am thinking gas will move faster than water so I would be looking at 1" or 3/4" if absolutely necessary. Maybe 1/2" but that has a much greater chance of creating issues. I assume code is 1.5"
Be careful how easy that flexible line can restrict flow as it bends.

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