I should have posted this first before my son and I spent two days on the problem
My son’s home lacked an expansion tank when the home was constructed
He has been living with a bomb for years
A $10.00 gage would have saved my son two hotwater tanks - two TPR valves - and two regulator
Thank goodness the whole tank did not blow like we have seen on MyTube
Once again put the pressure gage on the system and watch it as the tank comes up to temp
With a pressure regulator installed this is a closed system and the pressure can go to the breaking point
Thank you sir
I hope this information about watching the pressure gets to more inspectors - I never thought of it until it became an issue during my Xmas visit with the son and grand kids
And yes - I took my pressure gage with me to check the system
We thought it was a defective regulator until we had a beer or two and thought about it for a while
This is why the PRV should always be one with built in bypass, without the bypass the PRV acts as a check valve, not allowing expansion back through to the main.
The TPR should have protected the tanks and not allowed the pressure to build up more than 125 PSI. :?:
Pertaining to my “built in bypass” comment, let me back pedal a little because I didn’t read the “160 PSI” part. #-o
Naturally IF the incoming water pressure is higher than the TPR setting, the pressure in the system would relieve before it could overcome main pressure and back out to the street.
A built in bypass isn’t going to make a whole lot of difference other than prevent a closed system BUT still the pressure from expansion couldn’t get any higher than the incoming pressure and any water heater should withstand 160 PSI even IF the TPR valve failed.
Assuming a full sized drain on a properly working TPR valve, the pressure in the system could never get any higher than 125 PSI but a flooded basement - yes.