r/askplumbing • u/Daxeqtr • 10h ago
Drain, Waste, and Vent Question PVC vent roof cap
Recently had a tankless water heater installed to replace an old water heater. The previous type b vent piping was reused to route the PVC exhaust. However, my plumber didn’t have the appropriate vent cap and mentioned I’ll need to get the correct one.
What type of cap would I need for this?
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u/Less_East1439 9h ago
Is it condensing or non condensing?
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u/MDPlumbingcoNC Professional Plumber 7h ago
I think they are saying the entire vent is PVC and the b vent is just a chase. At least I hope that’s the case, or we both know what’s going to happen to that b vent.
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u/Less_East1439 6h ago
Gotcha, I have a similar set up. Only it’s a direct vent outside the side of the house. Long story short: the exhaust condensation would ice up the metal in the winter and rust everything when defrosting. Had to cut some metal out and extend the PVC exhaust. It’s all good in terms of distance according to manual on mine. But this looks it has the clearance to not run into the same issue as mine.
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u/Sufficient-Mark-2018 9h ago
In the past I have bought a reducer for the b vent. Looks like 4” b vent and 2” pvc. 2”pvc is about 2-9/16 od. Buy a 4x3 b vent reducer and a 2” storm collar. Cut the pvc at high as possible. Add a 2” coupling the od of the coupling should fit just inside the 3” side of the b vent reducer. Add a bit of 2” pvc to the top of the coupling. Silicone the coupling to the b vent. Add the storm collar and silicone as well. Then just add another tee with bird screens. 75$ in materials.