Hi - a few apparently random rads within a single zone have just stopped working. They have been checked for air (they're full of water). The pipe feeding one of them is hot at the on/off valve, but two others are cold at the valves. Our pressure dropped just before this happened, I adjusted it back to normal, and switched the heating back on and all seemed to be well, but then I discovered that these rads had stopped taking hot water in.
What could cause this - a build-up of sludge maybe? Will I have to remove a rad or two to check it (I have installed/moved rads before, so I can handle this!)? Thanks in advance for any help.
What could cause this - a build-up of sludge maybe? Will I have to remove a rad or two to check it (I have installed/moved rads before, so I can handle this!)? Thanks in advance for any help.