Home>Discussions>PLUMBING>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 have a FB-38 Bell and Gossett pressure reducing valve in my radiator system (a contractor just installed it 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

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

Rob,

I recommend that you leave things the way they are and immediately call the service person to get him back in there ASAP----in this type of situation it is so easy to touch the wrong thing and you end up with a flooded basement, or something worse-----the repair man's work comes with a guarantee that he has to make good on any work he does or he comes back right away to get it right.

If you touch the wrong thing while poking around down there the repairman may walk away from it & end up blaming YOU for HIS mess.

dj1
Re: Problem with my radiator's new pressure reducing valve? (any thoughts/clues) than
dj1

I would guess that you had a wrong pressure reducing valve installed. 10 psi is low, most common PRVs are 45 at a minimum.

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

It is very possible that the prv is ok but your expansion tank is defective. I would check that before getting my knickers in a knot.
Also the pressure on a heating system is set to over come the height of that system. Normally 1/2 psi for every foot from top to bottom. Heating Prv normally come set at 12 psi and we would leave them there as a minimum . 45 psi is for a domestic water prv and would blow the safety valve as heating systems should never go over 30 psi. EVER think boiler explosion.

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