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steam radiator vent leak

Hi experts, I've searched for answers as I imagine this is common, but haven't found the exact help I need. Apologies in advance for mis-use of terminology.

We recently turned on a radiator on our top floor for the first time (we're just renovating and using the room for the first time). Our plumber had to turn it on because the valve was stuck. The radiator heats up really well, but water is leaking from the vent. The water is coming not from where the vent screws into the radiator, but from the vent hole. It's enough to create a small puddle on the floor when the heat is high.

I've switched the vent twice, and tried to increase the pitch of the radiator (although I imagine if the pitch was wrong it wouldn't heat up at all?).

Don't have the problem in any other of our radiators. It's a single-pipe system.



  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,508
    leaking vent

    i am not familiar with that make of vent, however it may be one of those vents, which "spits like a llama"! see if you can find a hoffman radiator vent. they seem more spit-proof than most.

    if that doesn't cure the leaking, then check the pressure of your boiler, and get it set as low as possible [under 12 ounces is ideal, but requires a vaporstat]. in addition to the pressure, increase the capacity of your main line venting, so the radiator vent [and your gas company/wallet] doesn't have to do so much work.--nbc
  • paulrichard
    paulrichard Member Posts: 2
    steam radiator vent leak

    thanks nicholas.

    The PSI generally is at 3 on the boiler. Is reducing the pressure just a question of pushing the pressuretrol to 2 or 1, instead of 3?

    And one more question, is there a recommended style/brand of main line vent. I know ours needs replacing because it is completely covered with rust.
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