heat not working properly

mrgagnon

I have a 1 loop forced hot water system - the downstairs is fine - only 1 of 5 radiators upstairs are getting heat.  Pipes in basement are hot - I have vented the radiators.  Any help?

Rodman

flow

You seem to have a flow problem.  Make sure the valves are all wide open to begin.  These valves are near the floor, so just turn them counter clockwise all of the way.  The knob will rise when you do this.  Sometimes, when the valves are 3/4 or more closed, they can shut down the flow to that radiator, altogether.  If you have one of those houses where you get an imbalance of heat on the second floor, people will turn these valves down or off.

When you bled the system, did you start at the lowest radiator and go to the highest radiator?  Did you get water strongly flowing out of each bleed valve?

Air in the system can cause the water to not flow properly or at all.  Go down in your basement and feel the pipes that feed the second floor.  Feel them as far away from the trunk line as possible.  These pipes should all be hot (when boiler running) to the touch, both supply and returns. 

Have you changed the pump or circulator recently?  If you have 3 or 4 inch trunk lines in the basement, and all large radiators in the house, you may not have enough water flow.  I don't know how large your house is, but many of these old systems had a Bell & Gossett 100 (motor with a separate pump).  These have a very flat curve and can pump 6-8 GPM which may be needed for the system to work properly.  This last thought is the least likely, as it has not been that cold out thus far.

mrgagnon

no water

I bleed the radiator at the radiators upstairs, I got very little air and no water at all.

mrgagnon

no water

I bleed the radiator at the radiators upstairs, I got very little air and no water at all.  I checked the pipes in the basement they we all hot.  Will check the valves to make sure they are open

Paul48

pressure

What does the pressure on the boiler read? It sounds as though the supply to the auto-fill regulator has been shut off. You need a certain amount of pressure to keep the system full to the highest point of radiation.The auto-fill regulator is on the city/well water supply to the boiler. The normal pressures of domestic water supply are much too high for the boiler and must be regulated down to, in your case approximately 15 psi. Find the supply water for the boiler, and make sure it is open, then check the pressure on the system. Let us know from there.

mrgagnon

boiler pressure

Hard to read very low -  looks like somewhere around 5 psi  I think everything is open

Paul48

no good

Five psi is not enough pressure to push the water up to the second floor. That's why you got no water, and very little air out of the bleeders.

mrgagnon

what do I DO

So what do I do? How do I tell if pressure regular is working properly?

Paul48

read

See Above

mrgagnon

how do I tell if its open

Their is no valve on regulator - just a tab - what direction should tab be in

Paul48

valve

Look for a valve before the regulator

mrgagnon

all set

I am all set now thanks

SWEI

How long

Since that valve was last opened?  Could be interesting to know how tight your system really is.

Rodman

regulator

My regulator has a handle on the top.  If it is lifted, you can hear the water flow.  You can leave it open or up while you are bleeding the radiators, BUT YOU NEED TO HAVE SOMEONE WATCH THE BOILER AND SHUT THE WATER FLOW OFF EVERY TIME IT GETS UP TO, SAY 20 PSI.  Your relief valve is supposed to blow at 30 PSI.  Bleed the radiators from the bottom up, BUT the best time to do this is when it is warmer when the boiler has not been running.  Many boilers are setup with fresh water going right into the return at the boiler.  You do not want to crack the boiler.  It would be best to turn off the boiler for an hour or more and let it cool and then do this. 



It doesn't sound like your system has been properly maintained, and it needs to be checked, including the relief valve, check to see if the expansion tank is filled with water, and the water fill valve.  The water fill valve cost the better part of $100, and should be replaced periodically, especially if you are in a hard water area like me.  This can keep the valve from properly filling the boiler.  You do not want a low water condition for the boiler.



You mentioned the tab.  It probably is in the run or normal condition.  If you move the tab, you are basically opening the water line to the boiler to permit full flow for filling or refilling the boiler.