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Radiator Control Knobs - no numbers

Niroth Member Posts: 1

I am a renter using steam heat for the first time. My living room is the furthest room in the house from the boiler, so it ends up cold in the living rooms and VERY warm in the bedrooms where we would prefer it to be colder to sleep.

The radiators have the control knobs on top of the air valves but they are fairly old so the numbers that were painted on can't be read anymore. If I turn them (using a screw driver) while the burner is really trying to heat the apartment (like when I get home from work and turn the thermostat from 58 -> 68) i can hear the "hiss" noise get louder and quieter as I turn, but I'm not sure if I am turning it up or down.

I am guessing the louder hiss means more heat from that radiator, is this true?



  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,507
    louder hiss?

    yes the louder hiss is a sign more air is being allowed to escape, thus allowing the steam to enter the radiators. if you take that dial off, that should allow the maximum air flow. there may be problems with too much air flow, causing water-hammer. see if you can also find the main vents in the boiler room, and determine whether they are functioning properly, because it is they who should do all the work.--nbc
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