Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

System Pressure ?

Danscrew
Danscrew Member Posts: 130
in THE MAIN WALL
I'm Running a WM 97 with an internal expansion Tank my pressure has been 20 -25 psi . I added 18 feet of cast iron baseboard to the basement Loop my pressure went up to close to 30 when the water got hot around 125 Degrees (Condensing Boiler) . The 30 pound relief never lifted yet so do I need to add a expansion tank to the system maybe the internal is to small can I lower the pressure reducing valve to run the system at a lower pressure ? thanks Dan

Comments

  • hot_rod
    hot_rod Member Posts: 22,786
    Check the pressure gauge for accuracy usually they start to seep just under 30 psi. You might replace the relief valve if and when you replace the tank

    The fill valve may not be shutting off completely also
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    If it just happened after you opened the system and refilled it, I would make sure it was properly bled

    There was an error rendering this rich post.

  • ced48
    ced48 Member Posts: 469
    Maybe a dumb question, but why are you running with that much system pressure?
  • Danscrew
    Danscrew Member Posts: 130
    T
  • Danscrew
    Danscrew Member Posts: 130
    The gauge was changed and is brand new Reading the same as
    the last one, Everything is new 2 heating seasons old everything was bled no air in the system , I wasn't going to start changing things with a around 18 psi operating pressure give or take maybe the fill valve is leaking by I have to check that
  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    If you have the ability to keep an eye on it, why not close the fill valve completely, drop the pressure down the 12-15 lbs and see if it stabilizes. If it does, then open the fill valve and see if any water goes in-pressure goes up. The valve could not be sealing, the pressure could be set too high, or circulator placement could be dropping the pressure and allowing the valve to open and add water.
    Of course a low water cut-off should be installed.

    There was an error rendering this rich post.

  • Danscrew
    Danscrew Member Posts: 130
    Thanks Steve
    Before i read your reply i valved of the inlet and let the pressure off the system. What I think happened when i installed the system I took the Dual valve unit out of the box and installed it leaving it set to the factory setting. My bad A factory setting im sure is not set up with a 65-70 inlet supply pressure so if you increse the inlet pressure the discharge pressure will go up . A Pressure reducing valves discharge pressure is set according to the inlet pressure which for most of the time don't vary much. And yes it has a LWCO installed internal probe type
    thanks to all for your replies

Categories