fully pumped gas fired central heating system (S-type) in a two-storey house.
six radiators downstairs, 5 upstairs.
Problem:
One radiator downstairs doesn't heat up properly, all others are fine.
This radiator gets warm at the top, stays cold at the bottom. The input pipe (bottom right) is very hot to the touch, the output pipe (bottom left) is cold.
This is the furthest radiator from the boiler (downstairs) & pump (upstairs).
Attempts so far:
Assuming the radiator was sludged up, I removed it outside & flushed it through with hot water, top to bottom, bottom to top, all ways up, and got no sludge to speak of.
Whilst the radiator was disconnected, I opened the input valve and got a good pressure of very hot water. I opened the output valve and got a good pressure of cold water, which after a few second also got very hot.
Is it therefore safe to assume no airlock in return pipework / manifold ?
Refitting the radiator, problem still persists.
I'm now thinking that there may be too much back-pressure on the return valve, preventing proper circulation through the radiator. Does this seem likely ?
I'm planning to close all the other return valves except this one, to try to force a circulation through this radiator - is that a safe thing to do ?
Any advice or better ideas would be most welcome.
six radiators downstairs, 5 upstairs.
Problem:
One radiator downstairs doesn't heat up properly, all others are fine.
This radiator gets warm at the top, stays cold at the bottom. The input pipe (bottom right) is very hot to the touch, the output pipe (bottom left) is cold.
This is the furthest radiator from the boiler (downstairs) & pump (upstairs).
Attempts so far:
Assuming the radiator was sludged up, I removed it outside & flushed it through with hot water, top to bottom, bottom to top, all ways up, and got no sludge to speak of.
Whilst the radiator was disconnected, I opened the input valve and got a good pressure of very hot water. I opened the output valve and got a good pressure of cold water, which after a few second also got very hot.
Is it therefore safe to assume no airlock in return pipework / manifold ?
Refitting the radiator, problem still persists.
I'm now thinking that there may be too much back-pressure on the return valve, preventing proper circulation through the radiator. Does this seem likely ?
I'm planning to close all the other return valves except this one, to try to force a circulation through this radiator - is that a safe thing to do ?
Any advice or better ideas would be most welcome.