!. Shut the boiler off and let system completely cool
2. Go to the very last radiator and open the bleeder valve, leave this valve open
3. Go to the very first radiator and open the bleeder valve, allow water to flow out until there is a steady stream.
4. Go to the second radiator and continue the process
5. Go to each additional radiator and continue the process until you reach the last radiator. when the last radiator has a steady stream of water coming from the bleeder, close the bleeder
6. Return to the boiler but do not turn it on yet, Locate the high pressure pop off valve ( High pressure relief valve) and open it, leave this valve open until a steady stream of water comes out of the over flow tube. When you have a steady stream of water let it continue to run out for about 15 minutes to make sure all of the air has been purged from the system.
7. When you are certian all the air has been purged from the system close the high pressure relief valve and fire your boiler
8. After the system has built enough pressure to make steam heat locate the jocky pump (circulation pump) and make sure it is working properly. Your problem may not be air in the system, it may just be a bad circulation pump. If your circulation pump has gone bad or is not working properly then you will only get heat to the first one or two radiators in the line. Also if you have a very old heating system scale build up may have clogged the line.
If you have discolored water coming from the system when you bleed it then you need to flush the system until the water shows clear again. Boiler systems should be flushed periodicly to keep the rust and scale build up flushed out of the system.
Never ever turn the cold water make up valve on unless you are sure that the boiler is completely cold unless you want to blow up your boiler. Cold water will bust the tubes inside the boiler and possibly cause serious harm to anyone standing close by.
One last note: Never listen to idiots who have no experience with steam boiler systems unless you like taking risk with your life.
You also dont have to trust my advice, you can call an Industrial Steam Boiler Company and they will be happy to talk with you on the telephone. If you cant find one in your local telephone directory then call the nearest Manufacturing Company near you and ask the Director of Maintenance to recommend some one who services steam boilers.
Please post the type and model of your boiler. some systems are hot water systems and some are steam systems the procedure is differant for each. If you have a steam system instead of a hot water system then you will want to flush all of the trunk lines and then make sure all of the water is drained from the radiators and trunk lines before firing the boiler because a water flooded steam system will also only heat the first one or two rdiators in the line
25 years as an Industrial Steam Boiler Operator and Industrial Maintenance Manager/Safety Administrator
· 1 decade ago