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.

Oil residential Home boiler pressure

richardsonseanj
richardsonseanj Member Posts: 3
edited January 25 in Oil Heating

Hi All - I recently purchased a home back in the spring and this is my first ever time with baseboard hot water boiler heat. My boiler is a Weil-McLain Gold series boiler (we think installed around 2009). I had it maintenanced at the start of the season and about 3 weeks ago I called my HVAC guy and told him the pressure was at about 30-33 psi which seemed high. He came by (family friend, retired but does it on the side still) and released the old steel expansion tank - then added some new water to get the pressure around 12-15 PSI. I’ve noticed it keeps going down to around 10 psi and sits there. It doesn’t go below that but for some reason stays at 10. Should I be concerned? I was thinking maybe there’s a small leak in one of the levels (3 story house split level). The bottom level the pipes are in the slab but if there was a leak I’d think that it would drop to 0 - we manually add water vs a pressure value (he requested to ensures no leak). I haven’t noticed water anywhere. Just trying to understand the basics of why it stays around the 10 instead of staying at 15 (even if I add water)

Comments

  • Grallert
    Grallert Member Posts: 895

    Are you saying that you can't move the gauge when you add water? In reality 10 is likely good but it could also be the gauge is bad and settles at 10 as it that were zero. When you saw 30-33 you should have also seen water dripping or flowing from your 30psi pressure relief valve. With out more detail I would be suspicious of your gauge.

    Miss Hall's School service mechanic, greenhouse manager, teacher, dog walker and designated driver

    HVACNUT
  • richardsonseanj
    richardsonseanj Member Posts: 3

    it will go up and down but eventually resides back down to 10 psi - the HVAC guy ordered a new pressure value as we suspect it’s bad and was not releasing

  • HVACNUT
    HVACNUT Member Posts: 6,558

    So a steel expansion tank up in the rafters. Not a diaphragm tank. Are there any air eliminators attached to the boiler piping? There shouldn't be. What's in the 1/2" tap to the left of the supply outlet?

    I would think the relief valve did it's job if it discharged at 30 psi. That would also tell me the gauge is at least somewhat accurate if you know that's when it discharges. I don't see why you can't maintain 12-15 psi. Maybe get a second pressure gauge you can attach to a drain valve. If it's a high volume system, it might take more water to bring the pressure up.

  • richardsonseanj
    richardsonseanj Member Posts: 3

    My biggest fear is I heard that adding water to my boiler system can cause it to rust out and create leaks faster? Is this true? I added water last week to make it 15psi

Categories