Radiator

[langara]

We had a new valve fitted today, we thought the pump had gone as the radiators only got hot when the water was heating up, but the engineer said nothing wrong with pump, all going well except for one radiator which is still stone cold, hubby has bled it, but nothing, all other radiators piping hot.
Has anyone any ideas. Thanks

[Old_Geezer]

Control for that radiator actually working, and on max ? Is it cold from top to bottom ?

[ummmm]

Turn all the other radiators off and just leave the cold one on.

[The Builder]

The whole system may need balancing, although I doubt it if the other rads are red-hot, and only this one is stone cold.

Do what ummmm says, it should tell you a lot.

That rad may well be on a "dead leg" where air has stopped the water from flowing properly. This can happen if, for instance, a rad has been added at some point, and the pipework layout has been messed up.

Also, try increasing the pump speed for a while. It may just get things going again.

[boxtops]

I'm interested in this one - over Christmas the radiator in the bedroom at the top of the house (which is the highest one on the system) remained stone cold. We bled it and nothing came out (which in itself is not good news, usually there is a ssssh of air, then water) - should I call in the plumbers who maintain our boiler?

[The Builder]

Boxers .......... yours does sound like a suitable case for re-balancing. The other rads are pinching all the available hot water.

Often happens with loft conversions.

[mastercraft]

Does it have a thermostatic valve? Sometimes the valve sticks and a light (LIGHT) tap will free it. Remove the valves outer casing first!

[boxtops]

Yes it does, mastercraft :-)

[langara]

yes old geezer, stone cold, thought it may have righted itself overnight, but nothing this morning, hubby says it has a drain valve on it so going to drain it this morning.

[langara]

Thanks to all who gave advice on our cold radiator, this morning my hubby did two things, turned off all other radiators and also turned pump speed o full, and it worked, not sure which method worked but we know have a fully working radiator, he then also bled the naughty one and lots of air came out where as yesterday non came out. Thanks all hope our solution helps anyone else with the same problem.

[Old_Geezer]

But the toilet is working just fine.

Glad you got it sorted. I was expecting a stuck control.

[boxtops]

Welll..... we feel uninformed, but warm.... the plumber came, it was air in the pipes. When we bled the rad nothing came out, because the boiler pressure was too low to push the air up to the top of the house. OH knows how to tweak the boiler now, if it happens again!