Home>Discussions>INSULATION & HVAC>Problem with my radiator's new pressure reducing valve? (any thoughts/clues) thanks!
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oatbean
Problem with my radiator's new pressure reducing valve? (any thoughts/clues) thanks!
oatbean

Hi,

I had a new pressure reducing valve installed in my radiator system 4 days ago and the label on the valve says “Set at 12 lbs”.

Unfortunately, I awoke this morning to find water on the floor beside the boiler and still dripping (the pressure relief valve in action). The boiler's pressure gauge showed 30psi and the temp was 140F. I turned the thermostat down and allowed everything to cool during the day.

This evening (with the water temp below 60F) I closed off the system’s main water feed valve, bled the pressure down to 10psi. and then re-opened the main water valve. Within about 10 or 20 seconds, without adding heat to the system, the pressure gauge moved up to 20psi.

Isn't the function of this "pressure reducing valve' to keep the pressure at or below 12psi? Or, am I thinking about this wrong? It seems to me like they've installed a defective pressure reducing valve but I honestly don't claim to know very much about this stuff. Am I on the right track?

Sincere thanks! -Rob

NotAHandyman
Re: Problem with my radiator's new pressure reducing valve? (any thoughts/clues) than
NotAHandyman

I have a similar problem. Did you ever resolve this?

bill
Re: Problem with my radiator's new pressure reducing valve? (any thoughts/clues) than
bill

It sounds like you have a defective PRV. That being said there can be other problems with you heating system. For example your expansion tank could be defective, even with the prv closed water expands when heated and if the expansion tank can not take the extra water then the pressure will rise until 30 lbs and the safety valve open then the system cools and pressure drops to 5 lbs,
If some one is good they could re calibrate the prv if not buy a new 1450 f prv It should hold 12 lbs or enough pressure to get the water to the top rad.it should hold that pressure when cold, then close the water valve in front of the prv and turn up the tsat the pressure can rise some but if it goes over 20 lbs then the expansion tank is defective and needs replacing. I always like extrol 60. Buy one on and see if that makes a difference.

Bill

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