Is the Radiator Air-Locked?
If you have a hot-water radiator that’s not heating, the cause is usually trapped air. Getting rid of it is simple. Use a radiator key, 1/4-in. 12-point socket or a flat screw- driver (depending on your valve type) and slowly turn the valve counterclockwise until water drips out. This will release trapped air and let hot water flow. While you’re at it, repeat the process on your other radiators. Bleeding the radiators will lower the pressure in your system, so you might have to slowly add water to increase the pressure. Do this by opening, then closing, the valve on the water pipe above the boiler.
If you’re unfamiliar with your system, call a pro. How much pressure you need depends on how high the water has to rise. 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 two-story house, with the boiler and expansion tank in the basement, needs 12 to 15 lbs., or 25 to 30 ft., of pressure.
Cold House Solution 1: Electric Toe-Kick Heaters
Cold House Solution 2: Duct-Booster Fans
A ‘register’ booster fan is much easier to install. Depending on the model, it either sits on top of or replaces a floor or wall register grille, and plugs into an outlet. A built-in thermostat switches on when the furnace operates. Register duct boosters cost $40 to $70. Many different manufacturers make duct booster fans of both types. Search online for ‘in-line duct booster fan’ or ‘register duct booster fan’ to find manufacturers and dealers.