Have one radiator in an otherwise warm house not working. Have bled all the radiators and the others are piping hot, but the bathroom rad remains stone cold. Any ideas on how to solve this?
cheers

Check the lockshield valve is open on the bathroom rad. (the one you normally don’t touch, it normally has a smooth cap on it) Count the turns as it should be set to be balanced with the other rads, if its open return it to the original setting.

Similarly, if you’ve fiddled with the lockshield valves on other rads in the house then you may have unbalanced the system, meaning the water is taking the easiest route through rads closer to the boiler, and never gets as far as the bathroom rad. An easy check is to close the valves (not the lockshield ones, the ones with a knurled knob) on the other rads which will restrict the flow, if your bathroom rad then gets hot you will need to do some reading on radiator balancing, and adjust all the lockshield valves on all rads.

(P.S…I’m not a plumber!)

Either an air blockage somewhere in the pipework, or the worst outlook, a pipe blocked with lots of gunge.

It is usually the return pipes that have the problem. Air in the system can be really easy, or a right pain to get out. Firstly, turn off all other radiators, with the heating on. This should then give more pressure to the one faulty rad, and , hopefully, push out the air bubble.
If it is a blocked pipe, then a dose of central heating cleaner in one of the rads, then leave it for 2 weeks, then a drain and flush out. This should clear any blockages.
Try turning off all other rads first to see if it is an easily removed air lock.

Alan.

tried both methods but didn’t work , cheers anyway

Try turning off all the other rads in the house except that one and see if that will get it moving.

That often works if it’s not a serious prob. If it does, once it’s working it’s probably worth flushing the system out.

C