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Does a boiler pressure relief valve need replacement after a single leak?

casette
casette Member Posts: 8
Sorry if this is a dumb/rudimentary question. I had some issues with my hot water heating system last winter, and ultimately my older compression tank needed to be drained. My pressure relief valve leaked a little bit before the problem was solved, and I was told that it needs to be replaced if it leaks even once, as water passing through the valve may cause sediment deposits that can cause the valve to catch/become inoperable later.

This doesn't make sense to me, as the safety tag on the valve says that it needs to be tested yearly, which consists of manually opening the valve and confirming that water leaks through. If this is the case, wouldn't testing the valve ruin it, as letting water leak through presents the same sediment issues as the valve leaking because of too much pressure?

I did not replace the valve last year, and today I tested it and water came out. So I have started the heating system again today as it is starting to get cold after the unusually warm weather in the past few weeks. Is this dangerous and do I need to replace the valve?

Thank you in advance for your help.

Comments

  • Larry Weingarten
    Larry Weingarten Member Posts: 3,272
    Hello, Seems to me that if the valve doesn't leak and if it allows good flow when opened, it doesn't need replacing. But I do primarily domestic hot water ;)
    Yours, Larry
  • JUGHNE
    JUGHNE Member Posts: 11,042
    If they drip/dribble very long mineral build up can seal them from opening, but most of the time they will not shut off completely and continue the drip.
    If it has a good flow when you open it and then let it snap shut it should completely stop flow in a few seconds.
    I always hold them open a few seconds for a good flush, maybe a gallon or so of water.

    I do this on every boiler service call, once or twice a year.
    If anything this will make them open easier, perhaps even under 30 PSI.......IMO.......then if they don't seal, they get replaced.

    Just squeaking it open for a little flow does not flush it well.
    When you flush this your boiler water pressure may drop and your fill valve should add make up water to return the pressure.

    There should be an extension pipe screwed into this to take the discharge to the floor. If it is iron pipe it too can build up scale/rust.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,452
    What @JUGHNE said is 100% correct
    Boon
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,505
    What @EBEBRATT-Ed said is 100% correct. But For the price of the valve, - I would replace.
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
    newenglandsteamworks.com