Cold Convector after bleeding

T. Lyons

I've got a hot water/convector system in my house (circa 1953). One convector (the one in the main bedroom) was cold, at the beginning of the season, so I bled it and all the others. This convector stays cold, though, and now when I "bleed" it, water comes out, though it's cold and doesn't seem to be under much pressure. The pipes that feed this convector branch off the main loop in the basement. The pipes get cold about 6" off the main branch. Other convectors down the line are hot.
As far as I can tell, there is a blockage in the line, or the valve at the bottom of the convector is broken/stuck off (the screw turns, pretty freely, no change). Pressure in the system is pretty constant.
Anyone have any ideas for me, and, if it is the valve or blockage, about how much would I be looking at to get it repaired (rates in my area are about $60/hr.).

Thanks,
T. Lyons - troubled homeowner

George_11

check the temperature rise across the boiler.

If it is more than 15-20 degrees you may have insufficient flow. I just last week replaced a circulator for someone who noticed that the heat, although warming the house, was unevenly distributed. Their circulator probably never started since the previous season.

Mike

Mike T., Swampeast MO

Does sound rather like the valve is closed. This might be obvious but are you certain that the valve shaft itself is turning and that the handle isn't "stripped"?

Mark Wolff

Bleeding

It sounds like either the valve is stripped, or you still possibly have an air problem. Sometimes when bleeding a system, you get some air, then water. Additional air can still be trapped behind that water, so to properly bleed the system, try to get several gallons worth of water out (at least 5) or until you get hot water. If you bleed till you have hot water coming out and not just water, you will know at least one side has been purged, and that should be enough usually to kick any air trap you have. If the valve is bad, obviously you'll need to replace it. $60/hr is a good rate, we charge $70/hr and are considering raising rates. Time to change a valve out will run you anywhere from 1/2 hour to 3 hours, depending on what complications arise. Expect at least a 1 hour minimum charge.

T. Lyons

Thanks for the reply. To be honest, I don't know if the shaft is actually turning. If it is stripped, how do I get it out, or will that still mean replacing the valve?

T. Lyons

Thanks. Is there a way I can "pull" the water out? Like siphoning it? It's got automatic bleeders on it, and even when I take the canister on the top completely off, the water just sits there.

jim lockard

pressure

What is the pressure on the boiler check the gage should be between 12 and 18 Psi depending upon your house

D Logan Ireland Oil Co Inc

monoflow system

It sounds to me that you have a monoflow system. My first question would be has this main bedroom convector always been a problem or is this the first time. Secondly look at the supply and return piping for that specific convector. The distance between the two tees is important. Some pictures would be nice. How long is that supply run to the convector. Is the monflow tee heading in the right direction.Look for an arrow. These are some basic trouble shooting questions that should be answered before you should proceed. One more thing stop bleeding the convector if all the air is removed and your getting water only. Its not an air problem it appears to be a restriction or pressure problem.Refer to the Q&A Menu on this Web site and look under diverter tee hot water heating.