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Pneumatic Radiator on off valve

I have a problem with a steam trap leaking and would like to turn the radiator off until I can figure out the problem. I do not know how this on off valve works.


    EBEBRATT-Ed Member Posts: 15,827
    That's a pneumatic valve, it opens and closes with air pressure.

    Most (but not all) heating valves open with low or no air pressure and close with full air pressure.

    so , chances are if you put 15 psi of air pressure (which is considered full pressure) on the valve it will close. (no gauaranntee it will close 100% tight) You can also check its operation by turning the thermostat (or whatever controls the valve up and down)

    The tee with the plug in it is for a pressure gauge to check the air pressure at the valve.

    Turning the thermostat up and down should drive the valve open and closed

    That pipe plug is either 1/8" pipe size or 1/4" pipe size.

    Because it's only 15 psi you could disconnect the air line live and cap it if you have the proper fittings .pump up the valve with a bicycle pump is another way to check its operation