Settle A Heating Debate Lol!

[Smowball]

Ok, 3 storey house, lots of radiators. I turn the ones off in the rooms that aren’t really used much. As for the rest of the house, I turn the heating dial on till it just clicks on and heating comes on, then when house it warm enough I turn it down/off. Then hours later if I think it’s a bit chilly I might turn it up again. Mr smow says it’s more economical to keep it on low all the time in the day. i.e. turn the dial so it clicks and heating just comes on, then keep it like that all day. Which is best?? Or does it make no difference?

[Smowball]

They all seem to have cooled down apart from the main one in the lounge and that’s still really hot .

[Atheist]

Smow, it doesn't matter how hot the radiator is, but how warm the room is. If the room is too hot, then turn the TRV down a bit. If the room isn't warm enough then leave it until it reaches a good temperature and see if the rad starts to cool down (it will start to cool once it closes itself and stops hot water from arriving; it won't suddenly go cold - it's not like an electric fire, more like a kettle that's just boiled and talkes time to cool).

[Smowball]

Right ok, I must sound thick!! Ok, the long lounge doesn’t feel hot. The radiator one end is under the window and is fairly cool. The other end of the room where the dining table is, is the big radiator on one wall and that’s the red hot one.

[Atheist]

Smo - are both rads in the lounge fitted with TRV's? If so, are they set to the same number?
Does the lounge feel warmer at one end than the other?
Have you got a thermometer? If so, can you use it to check the objective temps, not the subjective ones. Make sure the thermometer is placed at the same height above floor level each time you use it.
If you find different temps at the same TRV number, then presume that the TRV numbers aren't necessarily accurate and allow for that when you choose a number to use.
All this will take a lot of time; it's not like turning on and off an electric fire. Work at it slowly with only small adjustments; it's a question of balancing the settings.
If you try some of the advice here you might learn how to tweak things so that the whole system behaves a bit better.

[The Builder]

Just a couple of things to add.
The problem with your lounge rads, Smow, and maybe some of the other symptoms, suggests the rads need balancing.
All that means is that some rads are being greedy. They use the available flow of hot water, and starve the others in the room.

As for the controls - the wall dial and the rad TRVs do very different jobs. I'm afraid that, by fiddling with them, you're just making things worse. Crudely speaking, they're trying to override each other.

Up until a few years ago, there was no requirement for a wall control. You just had TRVs on each rad. You set the "volume control" for each room separately using the TRV. It worked fine.
Then, the politicians decided they needed to be seen to contribute to energy saving.
They re-introduced wall thermostats. A stat that controls the whole house is useless. You just cannot "average" the whole building's temperature out. Personally, I would get rid of it, and just leave it to the TRVs. (Especially in a 3 storey house. The idea of something near the front door controlling the top floor is crazy.)

Without the wall stat, you can set each room's TRV by trial and error, and leave it at that.
For a lounge, just wind the TRV up and down to suit.

The boiler senses the returning water from the rads. If it's cool, the boiler comes on. If hot, it doesn't. But, only within your timer settings. It won't come on if it's being told that it's not time for it yet.

[The Builder]

Just realised... even after all that, I haven't answered your question.

YES, keep it on. If you don't want to go to the expense of disconnecting the wall stat, just turn it right up to "silly". It'll never get there, but it won't interfere with the TRVs.
Control the rooms with the TRVs.

Even with the stat on "silly", the boiler will NOT come on if the TRVs are telling that it's warm enough.

[Atheist]

Builder. I think room stats were around well before TRV's.

[AuntPG]

No one has asked smow if she has a combi boiler or a traditional one with immersion heater.

[Atheist]

And, Builder, I agree with your suggestion that you can let the TRV's get on with the job; that's what we do. Except that Mrs A keeps turning down the room stat when I turn my back.
I was going to give Smow a bit of advice from Swiss Tony:-
"Getting your heating system to give a satisfying result every time is like making love to a beautiful woman. First, make sure your TRV is well oiled and working properly; remove the head and check the prong by poking it with an appropriate implement. Then start to increase the demand for heat, but slowly, slowly, just a bit at a time so that you can judge the response. If things get a bit too hot, you mustn't overdo it - ease off the dial a bit until things have settled down, then start again, and above all take your time - these things can't be rushed........."
I could go on, but I musn't.

[Barsel]

No Athiest, you mustn't. You naughty boy. :-)

[The Builder]

Ha Atheist. I like it ;o)

Yes, at one time, a wall stat was all you had. As I pointed out above, it was crude and ineffective.
Then, someone invented TRVs for individual room control. Wall stats weren't needed....
... until someone made the dopey decision to re-introduce them.

Aunty... it shouldn't make any difference. For heating: combis and traditional boilers work much the same as far as control is concerned.

[AuntPG]

It takes more energy to heat an immersion heater from cold than it does to keep it at an acceptable temperature doesn't it?

[The Builder]

I was only talking about heating, Aunty, but yes, you're quite right.
A cylinder of water takes ages to heat up. If it's left on, (they are well insulated today), not much energy is required to crank them back up to temperature.

I've got an air source heat pump with a dirty great 6' high immersion cylinder. It's on constantly, so it never cools right down.

[Atheist]

APG, yes it does, but remember that when it is cold it is not giving off heat to its surroundings like a hot cylinder is. If you're away for a week then definitely it should be turned off.

[bentaxle]

Smow if you cant get the family to always close the doors you'll have a job ,

[bentaxle]

Sorry about that , got in a bit of a muddle somehow