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75 PSI relief too high?

Jopom Member Posts: 1
Home Inspector mentioned this, I don't want to bring it up to the association without some merit.
3-story building, 12 units, 1 weil-mclain boiler that heats all units and a large water heater...
Inspector said the relief valve was rated for 75 psi, yet the "MAWP" for the boiler is 50psi.
Is this worth mentioning to the association? I'm moving in and don't want any bad first impressions, although it'd help if I was a hero ;)


  • SlamDunk
    SlamDunk Member Posts: 1,487
  • Jamie Hall
    Jamie Hall Member Posts: 21,553
    I'm surprised the home inspector didn't lock that boiler out. If the boiler is rated at 50, then the pressure relief valve must not be rated at more than 50.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • KC_Jones
    KC_Jones Member Posts: 5,431
    It’s perfectly fine if they want to take a chance of blowing up the building. Seen those stories on the news of boilers blowing through the roof? These are the types of things that lead to that.

    You may also want to mention to them whoever is working on their system is incompetent.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    EBEBRATT-Ed Member Posts: 13,834
    If indeed the boiler is rated 50 and it's a 75lb valve it must be changed. Not impossible for a contractor to make that mistake but it is a stupid and dangerous mistake. relief and safety valves are the most important valves on any boiler....the last line of defense

    Do yourself a favor and take pictures of the relief valve tag on the valve and the boiler name plate and compare the two and you can show the other association members

    It is also not impossible that the inspector read the tag and nameplate wrong so double check it
  • Mike_Sheppard
    Mike_Sheppard Member Posts: 696
    What model Weil McLain is it?
    Never stop learning.
  • pecmsg
    pecmsg Member Posts: 4,199
    50# boiler is commercial..........

    Why is a Home Inspector even looking at that? Well out of his field!

    Shouldn't it be inspected by a licensed and insured contractor before being inspected by the JHA!
  • JohnNY
    JohnNY Member Posts: 3,206
    If someone put a 75# relief valve on that boiler I'll bet you buckets of money it's because there's been an ongoing problem with controlling the pressure rise of the system when the boiler is operating. I advise the building get someone to evaluate the expansion tank sizing and static fill requirements to start. After that, piping configuration, pump values, and dynamic pressure changes need to be verified.
    Contact John "JohnNY" Cataneo, NYC Master Plumber, Lic 1784
    Plumbing in NYC or in NJ.
    Take his class.
    EBEBRATT-Ed Member Posts: 13,834
    And if the boiler won't handle the needed static pressure after evaluation a heat exchanger, another expansion tank, water feeder, and pumps will fix it

  • Intplm.
    Intplm. Member Posts: 1,478
    I don't remember the model but I did a new Viessmann commercial boiler installation with a provided and recommended 70psi relief valve.
    Inspector did not pass the inspection. Was made to replace the relief valve. I don't remember why the relief valve was rated so high.