bleeding radiator does not help

Vasko Gjelaj

Hello, I own a 12 apt building in Yonkers, 3 floors with 4 apts. on each floor and I have been having problems with last apt.on 3rd floor (3D) and sometimes 3C. This is a baseboard hot water system. When I bleed the radiators apt 3C seems to be ok for a while The problem is apt.3D. Boiler pressure is set at 20lb but I usually raise it temp. before I bleed the radiator in 3D. Lots of air comes out in the proccess and then hot water appears. Then I put the presure back to 20lb. This process might work for few days and air builds up again with no heat. -I noticed that sometimes gas pilot fires few times and boiler goes on but sometimes it fires 20-30 times and then stops without turning the boiler on and then continues the same proccess few minutes later. It is set with Heat-Timer to go on every 5 minutes. -Is the pressure too low and perhaps at 25lb pressure it would push the air? -Could the automatic air vent(purger) be installed in boiler room, feeding or returning pipe so I don't have to bleed the radiators? (I do have the expansion tank) -Could the circulating pump be the problem? -Could that particular line be clogged up? What could be the problem?

c-rex

Bleeding

the radition won't help. You must replace the Humphery at once.

Glenn Harrison

Vasko, since you have ....

3 apartment buildings with hot water heat in them, might I suggest the first thing you do is click on the "books and more" section and order the book "Pumping Away". This will give you great insight as to how your boilers should be set up in terms of air seperator and pump placement, and WHY they should be where they should be.

Second, are any of the heating pipes in your buildings running thru a concrete floor? If this is the case, you may have a leak in the piping in the concrete, which is causing you to loose water in the system, which then causes fresh water to come in. Every time you intrduce fesh water into the system, you also introduce air into the system that is trapped in the water. As the water is heated the air separates from the water ane thenwill either leave thru the air eliminator if you have one, or it will go to the highest point in the system.

As far as your pressure goes, 20 psi should be enough to take care of a 3 story building. One quick way to check is to open a bleeder in 3D with the system at 20psi. If water comes squirting out, you have enough pressure. If it only trickles out of nothing at all, then you probaly don't have enough pressure.

As far as your pilot goes, it sounds like you have electronic igniton, and that most likely the igniton system needs to be cleaned as it sounds like the ignition control is not sensing the pilot being lit.

Hopefully this info will help you.

Glenn Harrison Residential Service Tech

Althoff Industries Inc. Mechanical and Electrical Contractors

Crystal Lake, Illinois