Hi all,
My first forum post is a plea for help! Sorry about the long message, I thought it would save wasting anyone’s time if I gave as much info as I could upfront.
One downstairs radiator in the hallway stays stone cold (the whole radiator and both the pipes cold) even though all of the other rads (5 downstairs and 6 upstairs) work fine and get very hot. It’s a gravity fed system, and there is water in the fill tank. I don’t think there is a TRV on the radiator, so no stuck pins.
The valves are ATC Myson Matchmaster+ and appear to be identical at both ends of the radiator. Inconvenient, because I have no way of knowing which pipe is the inflow, and which one is the return. I also don’t know the pipe routing in the house, so I can’t figure out whether the rad is at the start or the end of the loop.
I tried to bleed the radiator, but it wasn’t what I expected: a mixture of air and water (several litres in total) bled out for well over 2 hours before I got bored and closed the bleed valve again. I can’t figure out whether there is just a lot of air in the system, or whether air is actually getting in to replace the air coming out. None of the other radiators need to be bled (just water comes out immediately) and all continued to work fine both before and after I tried to bleed the one that wasn’t working. The radiator got slightly warm when I bled it, but cooled again afterwards – I imagine because the hotter water simply replaced the lost water, rather than because flow had returned.
I can’t see any way of inspecting the valves for blockages without draining the system. I rather suspect either a severe air lock, or a physical blockage of some description. Is there an easy way to tell the difference? I’ve tried turning all the other rads off to try to clear the air…
I really don’t know what to try next… I’m reluctant to drain the system because the rest of the CH works fine, so I don’t want to mess it up completely….
Cheers,
Ian
My first forum post is a plea for help! Sorry about the long message, I thought it would save wasting anyone’s time if I gave as much info as I could upfront.
One downstairs radiator in the hallway stays stone cold (the whole radiator and both the pipes cold) even though all of the other rads (5 downstairs and 6 upstairs) work fine and get very hot. It’s a gravity fed system, and there is water in the fill tank. I don’t think there is a TRV on the radiator, so no stuck pins.
The valves are ATC Myson Matchmaster+ and appear to be identical at both ends of the radiator. Inconvenient, because I have no way of knowing which pipe is the inflow, and which one is the return. I also don’t know the pipe routing in the house, so I can’t figure out whether the rad is at the start or the end of the loop.
I tried to bleed the radiator, but it wasn’t what I expected: a mixture of air and water (several litres in total) bled out for well over 2 hours before I got bored and closed the bleed valve again. I can’t figure out whether there is just a lot of air in the system, or whether air is actually getting in to replace the air coming out. None of the other radiators need to be bled (just water comes out immediately) and all continued to work fine both before and after I tried to bleed the one that wasn’t working. The radiator got slightly warm when I bled it, but cooled again afterwards – I imagine because the hotter water simply replaced the lost water, rather than because flow had returned.
I can’t see any way of inspecting the valves for blockages without draining the system. I rather suspect either a severe air lock, or a physical blockage of some description. Is there an easy way to tell the difference? I’ve tried turning all the other rads off to try to clear the air…
I really don’t know what to try next… I’m reluctant to drain the system because the rest of the CH works fine, so I don’t want to mess it up completely….
Cheers,
Ian
