Heating on, but some radiators switched off and still getting warm?

Gazelle1985

We leave some of our radiators off sometimes to save energy because the rooms don't get used all the time. However those radiators are still getting warm when the heating is on...some really hot, some just warm. We have a combi boiler - is this normal or is something wrong?

grumbler

If you switch them off with some valves, then these valves are faulty. As simple as that.

Albermarle

It is not normal. If you turn the radiator off, it should be cold, regardless of the rest of the house, combi boiler etc.
Normally one radiator can not/should not be turned off though.

ThisIsWeird

Hi Gaz.

Are you turning them off via their TRVs? If so, I guess they are knackered, to some degree. Either stuck pins, or failed heads.

Gazelle1985

Yes turning off via the TRVs. Will have to look into replacing them.

@Albermarle why shouldn't one radiator be turned off?

Albermarle

Gazelle1985 said:

Yes turning off via the TRVs. Will have to look into replacing them.

@Albermarle why shouldn't one radiator be turned off?

Because if all the TRV's ( when they are working properly) turn off, then the boiler is working but the heat has nowhere to go. I think you will probably get a better technical answer from someone else but AFAIK it is always recommended to have at least one radiator always fully on. I think traditionally it was the bathroom one, but we have our main kitchen one always on.

Gazelle1985

Oh ok, we always have several radiators on - there are just 3 or 4 which we turn off when we're working from home as we're not using the rooms.

Veteransaver

Are the trvs turned right off? And not just to the frost setting (snowflake symbol).
If they are right off then it will be a knackered valve or maybe some debris in the valve allowing a little bit of hot water through so you could try to dislodge by turning the valve on and off whilst the heating is pumping.
Which pipe to the rad is getting warm, the one with the trv on it or the other one?

Veteransaver

Albermarle said:

Gazelle1985 said:

Yes turning off via the TRVs. Will have to look into replacing them.

@Albermarle why shouldn't one radiator be turned off?

Because if all the TRV's ( when they are working properly) turn off, then the boiler is working but the heat has nowhere to go. I think you will probably get a better technical answer from someone else but AFAIK it is always recommended to have at least one radiator always fully on. I think traditionally it was the bathroom one, but we have our main kitchen one always on.

Depends whether the system has a bypass valve fitted. Boiler will just trip out normally anyway if it gets too hot so shouldn't be too harmful to the boiler.

Gazelle1985

Veteransaver said:

Are the trvs turned right off? And not just to the frost setting (snowflake symbol).
If they are right off then it will be a knackered valve or maybe some debris in the valve allowing a little bit of hot water through so you could try to dislodge by turning the valve on and off whilst the heating is pumping.
Which pipe to the rad is getting warm, the one with the trv on it or the other one?

They're turned off as far as they can go (which is the snowflake - all radiators are the same, but most work fine).

Weirdly one of the radiator pipes which is faulty is hot on the TRV side and the other is hot on the non-TRV side.

ThisIsWeird

I presume you have a wall 'stat in a room, ideally the sitting room? The rads in whatever room the stat is mounted should have normal valves and be always on. That's how the stat controls the temp, and the rads also act as a bypass, if needed.