Not sure if this fits here but I just repair a Lochinvar 750 copper fin pool heater. Replaced user interface and 3 gas valves. The parts failed due to flue gas leaking into the cabinet. I found it to be extremely excessive and I found that even with the sealing I did in these photos I ended up using an entire tube of RTV to seal it completely. I read the venting section in the manual and it all checks out but this seems like even with my repair th issue will come back. Something seems wrong to me curious if anyone has encountered this or has any insight.

Posted by Dick. C at 2021-02-18 16:58:57 UTC