HOW TO BLEED YOUR RADIATOR THE RIGHT WAY
A warm radiator on a cold day is like a hot cup of cocoa, welcoming you and thawing your frigid digits. When air gets trapped inside a radiator, hot water can’t flow through and the radiator turns to cold steel. Getting rid of that trapped air is simple.
At the top of your radiator, on one end, sits a small metal valve. If this valve has been painted over, carefully chip that paint off with a knife or small screwdriver. Now find your radiator key; you’ll need it to open and close the valve. You could also use, depending on the radiator’s valve type, a 1/4-in. 12-point socket or a flat screwdriver.
Using whatever tool works best on your radiator valve, slowly turn the valve counterclockwise. When you hear air hissing out of the valve, you’re fixing the problem. Hot water will push the air out to refill the cold radiator, and when that water starts coming out of the valve, close it tightly.
Bleeding air from your radiator might lower your system’s water pressure, and you may need to slowly add water to increase the pressure. In fact, you may need to add water while bleeding the radiator to help purge the air from the system. This is where a helper will save you trips up and down the stairs.
If you’re unfamiliar with your system, call a pro. How much pressure you need depends on how high the water must rise in your home. The basic rule is 1 lb. of pressure for every 2 ft. of rise. Your gauge may read in pounds, feet or both. A basic twostory house, with the boiler and expansion tank in the basement, needs 12 to 15 lbs., or 25 to 30 ft., of pressure.