hot water build up in water system

[DT plumbing]

Hello Everybody;
This Is Derryn the plumber with a question
I have a customer that has hot water build up pressure
I have installed a new PRV, The problem still exist
Should I install an Expansion tank on the HWT
I am wondering if this will stop the problem
dtvansickle@hotmail.com
Thanks Derryn

[SewerRatz]

Hello Everybody;
This Is Derryn the plumber with a question
I have a customer that has hot water build up pressure
I have installed a new PRV, The problem still exist
Should I install an Expansion tank on the HWT
I am wondering if this will stop the problem
dtvansickle@hotmail.com
Thanks Derryn

If there is a PRV on the system you must have an expansion tank.

[hj]

The pressure should build up in the entire system, not just the hot water, unless there is also a check valve on the line to the water heater.

[seaofnames]

You are a plumber and you dont know you need an expansion tank after a PRV?

I'm sure you could have done some more trouble shooting before asking here!