Lochinvar Power-fin relief valve setting

steamfitter

I am checking out an installation of 2 lochinvar power-fin condensing boilers in a boiler room on the roof of a 2 story building. They have relief valves set at 50 psi. I'm wondering why they're not 30 psi. Thoughts?

JUGHNE

Commercial boilers? What does the nameplate say?
Did the relief valves come with the boilers?

Gary Jansen_4

50 lb. relief valves are the standard relief valve that comes with all current Power Fin boilers.

steamfitter

So the 50 lb relief valves are standard with Powerfin boilers?
I'm guessing it allows for that boiler to be used in the basement of a building that requires the PRV to be set at a pressure higher than 12psi (ex: 30 psi) due to the height of the system.
Question: If you have a 2 story building and the boiler is on the roof, and you only need 12 psi on the PRV and Expansion Tank, is it a waste of money to buy and install 30 psi relief valves?
If a problem occurs down the road and the pressure climbs to 30 psi, a leaking relief valve would alert maintenance before it gets to 50 psi. Does that even matter?

delta T

My state boiler inspector (CO) requires an ASME rated expansion tank to be installed on any boiler that has a relief valve rated over 30 psi. Might be worth asking your AHJ to check and see. ASME tanks are not cheap at all.....