Temperamental radiator

[Linda tanner]

we had a new central heating system installed in June 2017.we noticed that one of the bedroom radiators keeps cutting out.we called the engineer out who lubricated the pins and it come on.if you turn the TRV thermostat on and off it does that but soon goes off again.we called the engineer back out who replaced the TRV thermostat.it is still doing it.the pipe leading to it is hot but something is stopping it going through.this engineer explained how the valve works and it got me thinking.this radiator is the only one that is behind a door.could that be the problem?is the TRV thinking it is warm enough.

 

[ShaunCorbs]

easy way to test take the head off the trv for a day does the rad stay hot?

 

[jtsplumbing]

Also possible that something is wrong with the radiator, something is inside stopping the flow of water, when you say new system was that new pipes, radiators etc.

 

[Gazzzz101]

Is your Boiler an erp?

 

[Darren Jackson]

Is your Boiler an erp?

Why does it matter?

 

[Gazzzz101]

We have had a few with similar issues recently not heating after installing erp combis on existing systems, the pump can sense resistance and will modulate like a gas valve so won’t force water through the furthest or hardest rads, so the only way to cure is to isolate all other rads apart from the ones in question and leave the heating running for 15 mins. This was Worcester’s advice regarding a 30i erp with similar problems.

 

[ShaunCorbs]

We have had a few with similar issues recently not heating after installing erp combis on existing systems, the pump can sense resistance and will modulate like a gas valve so won’t force water through the furthest or hardest rads, so the only way to cure is to isolate all other rads apart from the ones in question and leave the heating running for 15 mins. This was Worcester’s advice regarding a 30i erp with similar problems.

So an air lock nothing to do with the boiler

 

[Gazzzz101]

Just trying to help going off our past problems.

 

[Linda tanner]

We removed the TRV yesterday afternoon and it hasn’t gone off so that answers that but can we just put a normal thermostat on there?

 

[Darren Jackson]

You could put an ordinary wheel head valve on it yes. But it would not meet current standards. TRV's do not perform well when covered up by radiator cabinets, in closed spaces. Near a draft or located near another heat source. You could try putting the TRV on the other side of the radiator or by swapping it for a remote one. Or even just putting it on horizontally instead of vertically to take the sensing head a bit further away from the radiator if it is behind a door or an enclosed space with no air movement.