Single radiator not heating up

Joined
21 Aug 2022
Messages
10
Reaction score
3
Country
United Kingdom
Hi all,
I've just moved into this house and the living room radiator isn't heating up. I've searched through the internet with a lot of guides but it seems (at least in my unexperienced opinion) that my problem is a little unique.

This living room radiator doesn't have a TRV - both sides have the little caps which covers 2 lockshield valves. These valves are both fully opened (turned anti-clockwise). This radiator is controlled by one thermostat also in the living room (I'm assuming this but I think it makes sense), whereas the rest of the radiators in the house are controlled by a thermostat in the hall. The other radiators all heat up fine.

I've tried bleeding the radiator, but water comes out immediately. The pipes at either end don't heat up at all when I put the thermostat to a high temp but I can hear the boiler working when the thermostat screen indicates the little ignite sign to show it's trying to heat up. I've been playing around with it and noticed that the boiler also displays the heating signal when I switch on the living room thermostat (with the hallway one off).

I'm a complete novice when it comes to this stuff and I'm figuring out how to balance the radiator to see if that's the issue, but I'm not sure if there's anything specific I need to do since this radiator is controlled by the one thermostat - would I need to close off the lockshield valves on all the other rads and turn on the hallway thermostat as well? I also have a combi boiler if that makes a difference.

I've already asked around on the internet and I'm fairly certain I'll need someone to come look at it, but thought I'd ask here before that

Thanks
 
When you switch on the living room only stat does the boiler actually fire up and continue to run? Ie does it behave the same as when you switch in the hall only stat?
 
If you have 2 thermostats, then I’d say you have 2 motorised valves, so as per John, is the boiler actually firing up?
 
Yes - When I switch on only the living room one, the boiler status changes from 0 to C and intermittently flashes a blue light, same as the hallway one would if that was on
 
Rad valve stuck shut?
Been above 20c for months and thermostatic valves shut and stay stuck shut.
Can tap tap them and shock will often release the pin. Look up how online.
Then water will flow
 
Rad valve stuck shut?
Been above 20c for months and thermostatic valves shut and stay stuck shut.
Can tap tap them and shock will often release the pin. Look up how online.
Then water will flow
OP has stated not TRV’s.
This living room radiator doesn't have a TRV - both sides have the little caps which covers 2 lockshield valves. These valves are both fully opened (turned anti-clockwise). This radiator is controlled by one thermostat also in the living room (I'm assuming this but I think it makes sense), whereas the rest of the radiators in the house are controlled by a thermostat in the hall. The other radiators all heat up fine.
Thanks
 
Does it get hot if you put both thermostats to on?
No - only the rest of the radiators get hot.

There is another radiator with 2 lockshield valves in the house and the rest have TRVs - I turned them all to 0 and also shut the other one with 2 lockshields and it still doens't get hot with both thermostats on
 
Do you know if it heated for previous homeowner? It could be piped up wrong, or kinked if plastic. Also what boiler/system are we talking?
 
Had one like that. Sludge in rad. Came out like a sausage it was so badly blocked up.
Also have had valves corrode inside closing off flow.
Need a plumber to come look at it.
 
Yep, think I need to get an engineer to have a look - just tried to switch on the problem thermostat this morning and the boiler's not reacting at all now
 
Locate and open the living room motorized valve manually then fire the boiler by using the other roostat, see if living room rad gets hot, if it does then fault with motorized valve actuator.
 
Locate and open the living room motorized valve manually then fire the boiler by using the other roostat, see if living room rad gets hot, if it does then fault with motorized valve actuator.
I just tried that - the pipe for the living room motorised valve gets hot, but the radiator still stays cold including the 2 pipes at each end. I only let it run for ~5 minutes though, I will try to run it a bit longer and see if there's any difference

edit: Just to note, I had to look up what the motorised valves are to see what I was looking for, and it looks like there should be some resistance when I pop it to manual - it was almost completely smooth on mine, and it doesn't default back to the 'auto' side when it's unclipped from the manual edge
 
Back
Top