Welcome to Q&A for Home Maintenance Q&A section, where you can ask questions and get answers from me and other members of the community.

Spam, self-promotion, questions with abusive, inappropriate language, and irrelevant questions will be deleted.
All of the questions are moderated!


You'll be notified when your question is answered. Please reply with Feedback to share whether a solution worked or didn't work. Thank you!

Connect on Google+
Find on Google+ Local

noisy power vented water heater PVC vent pipe in cold weather attic area

0 votes
Power vented hot water heater PVC vent pipe passing thru attic knocks loudly in cold weather.
asked in Heating and AC by john-dephillips (120 points)
edited by darekrudy
Share this question on your favorite network.

1 Answer

0 votes

 

Hi John, 
 
This could be due to expansion of the WH’s PVC vent pipe. You can check its run at penetrations (ceiling, roof, any attic floor boards, etc,) and see if it’s tight at any of them. If it is tight, every time the warm exhaust gases start flowing through the pipe, PVC starts expanding and rubbing against those surfaces making noise. This could be happening as it is contracting / cooling down as well.
 
You should also check for tightness all WH’s PVC vent pipe joints (if there are any in your attic).
answered by darekrudy (21,730 points)
...