Sometimes, after you have let your boiler sit for long periods of time without being used, air can make its way into your boiler. If your boiler is not starting up or heating up right away, you may need to bleed the air out of the radiator. Just follow these simple steps to do this job yourself.
Gather Your Supplies
You are going to need to find your radiator key. You are also going to need to grab an old cloth as well as some old towels or plastic in order to bleed the boiler. If your boiler has nice flooring under it, you are going to want to put down a plastic drop cloth to catch any water in case it leaks.
You are also going to need a radiator key. If you don't know where yours is at, you can purchase one at your local hardware store for your radiator.
Protect Your Flooring
Next, you are going to need to protect your flooring. You are going to want to take the plastic drop cloth and lay it on the ground around your radiator, so that way if it is protected if water leaks out while you are draining the radiator. You may even want to put a towel right under where the opening for the radiator key is located.
Use The Key
Locate where you insert the radiator key. Put on solid work gloves and grab a hold of a cloth. Take the radiator key and insert it into the opening. Turn the key a quarter turn in the counter-clockwise position with one hand and hold a towel under the opening with the other hand. When you turn the key, you should hear a "hissing" sound; it may be rather faint, so try to minimize other sounds in the area so that you can focus on hearing this sound.
Your radiator should continue to produce a hissing sound until all of the air has exited your radiator. You will know that all the air has been released when the hissing sound stops and water starts to come out of your radiator opening instead of air.
When water starts to come out of your radiator, turn the key a quarter turn in the clockwise direction; you are basically doing the reverse of what you did earlier. This should close the radiator valve.
Your boiler should work more effectively now that you have bleed the excess air out of the lines. Make sure that the pressure is consistent throughout your radiator; if it is too low, you are going to need to adjust it. For more tips, contact a heating contractor.