Unusual issue - one radiator has stopped heating

[Springmachine]

We have 5 radiators in our house, one is a towel radiator in bathroom.

All have been working wonderfully until the bathroom one stopped getting warm.

DH went around and bled the radiators, lots of air came out and so the boiler was then topped up.

Yet still the bathroom radiator is stone cold whilst all other rads are hot.

It's unusual to me as the bathroom rad is closed to the boiler (combi) and I just assumed the heating went to the bathroom rad first and then onwards.

I've also noticed that the tiled bathroom floor which you can usually feel a warm patch where the pipes are is no longer warm.

So it seems there is no hot water getting to the bathroom rad at least a few feet before.

I'm assuming it's some type of air lock?

But how can we fix?

I'm a little worried it's going to be tiles up

either there is a leak (which you'd know about) or there is still air trapped. Try re-bleeding all the rads.

I suspect that you have thermostatic valves and if so after a period of time they can become stuck and no water will flow. You can vent them as one end will be connected ot the heating circuit but there won't be a through flow.

If you have got them unscrew the body and you will find a small pip sort of thing give that a press or tap it gentley and it might pop back up and then the water will flow and heat be restored unless someone has turned a conventional valve right down.

Worth a try or post a picture here worth a gaziollion words:)

Turn off all the hot ones. Does the cold one heat up?

I have a feeling that you have a small feed and expansion tank in the loft. Is there any water in it? How deep is the mud?

It's a combi, decent feed, no tank. Combi was new last year and we put in a larger Worcester one in case of future extension.

Il post some pics of rads

This is the rad in bathroom that's not heating

All other rads look like this, only this one in bedroom has thermostatic valve.

We tend to control heating from online app rather than adjusting radiators individually since they are set to the correct levels.

If you are anxious about losing the knob settings, count the turns as you close them and write it down.

Any that were open one turn or less, note it to the nearest quarter-turn.

Any that were open two turns or more, just write "too wide." When you re-open them later, start with one turn.

Thats the gubbins. Unscrew the "head" of the valve thats done by the metal ring with the upright grooves in it just under the plastic head of the valve there will be a small metal tip or spigoht there to move that up and down with a parir of pliers once its freed off screw the plasctic valve head back on make sure the valve is opmn and the heat will flow again. Done a few of them over time!.

Don't worry re the claibration settting.

Thanks for all the advice.

I'm a bit of a novice and not the tools to hand.

I remembered the radiator and valves have a 10 year warranty so I emailed the company and they have asked me if the pipes are hot to the radiator which they are not.

They emailed back straight away saying that as the pipe is cold that it's not a faulty radiator or valve and that it's something wrong with my pipes or boiler.

I have asked a plumber to take a look tomorrow but I have played around with the valves again on the radiator and one turns fully and the other one only a few degrees and seems stuck in a way.
I told the radiator company this but they still said it's a pipe or boiler fault.

I assume that if the plumber arrives and says it is indeed a valve problem that the radiator company won't believe it or help

"Turn off all the hot ones. Does the cold one heat up?"

Please do that. It will cost you nothing but ten minutes of your time.

I had the identical problem including cold pipes and it was a valve problem. The engineer came yesterday and took off the thermostat knob, turned the valve underneath on full (which doesn’t bother me as I always leave it on full blast) and is coming back with a replacement knob next week. It took him less than 10 minutes.

Therefore while I know nothing about heating systems, I can say from personal experience that the whole ‘cold pipes means the problem is with the boiler / pipes’ argument is rubbish.