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Help! Water baseboard boiler stuck at 30 psi!

I had a new Weil Mcclain cgt gold boiler with domestic coil installed 3 years ago. Since then we have had both zone valves replaced, and just a few days ago the actuator replaced. Our psi is supposed to be at 12 to 15. Since the new actuator was placed it has been doing up to 30 psi which triggers the water relief valve to open. We have gotten all the air out of the system, and have even drained water out of it and it is still sitting at 20 to 30 psi. Could the expansion tank be bad or the domestic coil have a pin hole? Any advice to why this is happening and how to fix this would be appreciated!

Comments

  • Paul48
    Paul48 Member Posts: 4,469
    Was that installed by a legit company, or handyman?
    ssh4creed
  • ssh4creed
    ssh4creed Member Posts: 7
    Paul48 it was installed by a company, but they will not come back. It took them over 14 hours for the initial install then 6 days to heat and hot water after. They will not come back. This was installed 3 years ago by Accurate Air out of Dover, PA.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,068
    Possibly the installer of the actuator:
    1 Overfilled the system
    2. Could be a bad expansion tank
    3. MU water PRV could be leaking buy
    4. Maybe he left a valve shut.


    Who installed the actuator? Have them come back.

    If I had installed the boiler I would not have been proud of it.

    Try "find a contractor" on this website
    ssh4creed
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,068
    City water feed= MAKE UP WATER
    ssh4creed
  • ssh4creed
    ssh4creed Member Posts: 7
    We let water out thinking that the system was overfilled. The tech that came out to put the actuator in from Strine heating said he isolated the actuator and only drained that part of the system. All the valves are open, and when we doing the knocking on the expansion tank it sounds like it should.
  • Jamie Hall
    Jamie Hall Member Posts: 24,100
    It is very difficult -- particularly with the modern bladder style tanks -- to determine if an expansion tank is properly charged by knocking on it. The only reliable way to find out is first, pop the Schrader valve just a bit -- only air should come out. If no air comes out, or water comes out, it's bad. If no air comes out, try isolating and draining the tank, then pressurise it with air to the intended system pressure and reconnecting it to the system and see what happens (if water comes out in the first test, the tank is toast).

    However, in your situation, I'd be more inclined to think that the PRV is leaking by. Close the shutoff valve from the domestic water to the system (you do have a shutoff?) and drain the system down to the correct pressure -- leave the shutoff shut off. If the pressure holds, it's the PRV.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    HVACNUTCTOilHeatssh4creed
  • vibert_c
    vibert_c Member Posts: 69
    @Jamie Hall However, in your situation, I'd be more inclined to think that the PRV is leaking by. Close the shutoff valve from the domestic water to the system (you do have a shutoff?) and drain the system down to the correct pressure -- leave the shutoff shut off. If the pressure holds, it's the PRV.

    Read this once again, and pay attention to the last three words.
    I'd like an explanation of who has finger trouble, or a brain fart, please.
    ssh4creed
  • Jamie Hall
    Jamie Hall Member Posts: 24,100
    vibert_c said:

    ...

    Read this once again, and pay attention to the last three words.
    I'd like an explanation of who has finger trouble, or a brain fart, please.

    @vibert_c How's that again? Perhaps I should have been clearer; I'm presuming that there is a pressure reducing valve on the feed to the system, which I abbreviated as "PRV", and is the valve to which I was referring. My apologies for the confusion.

    I do not think that either "finger trouble" nor "brain fart" is a particularly helpful way to point out a misused abbreviation.

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    HVACNUTCTOilHeatssh4creed
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 16,068
    And yes, If you have a tankless coil or an indirect water heater that could be the problem. Try shutting off the water feed to the tankless or the indirect heater if you have one and see what happens

    @Jamie Hall I don't understand. I thought your post was crystal
    ssh4creed
  • ssh4creed
    ssh4creed Member Posts: 7
    We manually brought down the pressure by releasing water out of the system down to 16psi, then shut off the valve to the feeder and it held steady so we are now thinking it's the automatic fill valve. We researched it and on boilers when there is a leak, they can go bad. Does this makes sense to anyone?
  • ssh4creed
    ssh4creed Member Posts: 7
    Also we are thinking it might be the house pressure reducing valve? Once again sorry thoughts?
  • Jamie Hall
    Jamie Hall Member Posts: 24,100
    ssh4creed said:

    We manually brought down the pressure by releasing water out of the system down to 16psi, then shut off the valve to the feeder and it held steady so we are now thinking it's the automatic fill valve. We researched it and on boilers when there is a leak, they can go bad. Does this makes sense to anyone?

    Exactly what I was talking about. Automatic feeders do sometimes decide to leak by, and it doesn't take much.

    Boilers which are constantly refilled with fresh water can have a real problem with corrosion and leaking, but that's mostly for steam boilers where the steam is wandering off somewhere, or where there is an elderly wet return which has started leaking. Not usually a problem with a hot water system like yours, unless there is a real honest to goodness leak somewhere in the piping - which you would probably know about.

    On the house pressure reducing valve. If the pressure at your faucets and all seems reasonable -- it doesn't knock the glass out of your hand! -- you're probably OK. However, I hope that if you have a house pressure reducing valve you also have an expansion tank somewhere on the domestic water system?
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
    ssh4creed
  • ssh4creed
    ssh4creed Member Posts: 7
    Here is a photo of my system for reference....
  • ssh4creed
    ssh4creed Member Posts: 7
    I honestly don't think it's the feeder, we did a little test where we shut off the valve to the boiler last night. Drained water out to 10 psi then left the valve off to see if it would fill and it didn't.
  • ChasMan
    ChasMan Member Posts: 462
    edited December 2017
    With pressure issues, the first thing I do now is make sure I have a gauge that works. Unless it was a brand new one, I would not trust yours at all. I have one that goes on a hose bib that I keep in the boiler room. Since your relief valve is popping though, we can assume the gauge is probably working ok for this purpose.

    That aside, your last post didn't make any sense to me. You say you shut off the feeder and drained it down to 10 PSI, Ok, that part makes sense. You introduce some air when you do that though and without the feeder valve on, there is no way to get makeup water to replace that air but that's ok for a bit.

    Then you said left the valve off to see if it would fill and it didn't. That is where it got confusing for me. Perhaps the misused PRV acronym / feeder / automatic fill valve is where I got lost.

    With the valve to the boiler is shut off, how would it fill? Those pressure reducing automatic fill valves are very reliable and last for years and years normally. But like with anything, you can get a dodgy one. If you leave the boiler fill valve off and the pressure sits at 10 PSI (approx.) and does not continuously rise over-night and then turn the fill valve on and it starts to rise, that is indicative of a mal adjusted or mal functioning Pressure reducing (automatic fill) valve.

    And you didn't answer the question about the house pressure side of things. When the house pressure swings a lot, the auto fill valve may not be able to cope indicating the house side pressure reducer or expansion tank is messed up but we don't even know if you have that setup. If your trusting the city with your house pressure it is a good idea to have a pressure gauge you can at least see what it is.

  • ChasMan
    ChasMan Member Posts: 462
    Just another observation, if that boiler is only three years old, you have a leak somewhere. Mine is 10 years old now and there is not one spot of rust on the black pipe, yours looks like it has been at the bottom of the ocean for a considerable period.