No room thermostat, is this right?

[tim.....]

My central heating has individual thermostatically controlled valves on each radiator.

I was given to understand that it was necessary to have one radiator without a valve, near to a room thermostat so that the boiler will be turned off when the room(s) reach the required temperature, to avoid very hot water being cycled around just the pipework.

But in the (recently refurbished) flat that I have just moved in to, there are thermostat controls on each rad and no room stat. Is this a correct installation for the current state of the art?

The boiler is hidden away in a cupboard, so it can't be integrated into the that as the cupboard will not be at 'room' temperature. I tend to have my radiators set low as I don't like warm rooms and I wouldn't want to blow up the boiler (not that it's my problem if it's the numpty landlord who's responsible for yet another wrong installation [1])

It's a combi bolier if that makes any difference (an Ariston Combi A)

tim

[1] there a list!

[dennis]

It shouldn't blow the boiler up, however it wastes a lot of gas and electricity if its running the pump and boiler when no heat is required.

Maybe it has an outside stat or a wireless one hidden somewhere?

[tim.....]

As it is me who should be selecting the temp, what is the point of hiding it?

tim

>

[Anita Palley]

Because the landlord has good reason not to trust you.

[tim.....]

It's my gas bill

tim

[Anita Palley]

That's exactly the sort of attitude he's talking about.

[tim.....]

Eh

You misunderstand (I think)

I am renting the whole flat with responsibility for all bill. If he didn't want people to be able to adjust the settings on the central heating he should have stuck with electric heaters.

Tim

[dennis]

To set the minimum temp you can run the heating?

[Martin Pentreath]

I lived in a flat like this - it's probably more a lazy heating engineer at fault than the landlord. They sometimes try to persuade people that room thermostats aren't necessary when you have thermostatic valves, but as Dennis has pointed out, this is not the most efficient way to run the system. In fact there is a stat in the boiler but it measures the temperature of the water circulating, not of the room, so the boiler does shut off once the water circulating reaches the temperature set. Once the rooms are up to temperature and the thermostatic valves shut off, the water in circulation will very rapidly heat up, because there is very little scope for heat loss, and the boiler will shut off for that reason. However, the pump will carry on running so there is some wasted electricty, but it's probably not anything to lose sleep over.

One way to control the temperature if you find that the valves aren't doing a good job is to adjust the temperature of the circulating water (as opposed from the water coming out of the taps, that will be a different knob). If the place is too hot turn down the temperature of the rads (although be aware that this means it will take longer for the place to heat up).

Cheers!

Martin

[Roger Mills]

If the system has been installed recently, it needs to comply with current regs - which means that there must be a 'boiler interlock'. This means that there must be some way of turning the boiler off completely when the heating demand is satisfied - rather than continuing to cycle it on its internal thermostat. The usual way of achieving this is by means of a room thermostat - installed in a room whose radiator does *not* have a TRV on it.

I have heard of an alternative way, using a flow switch, which switches everything off when the flow falls below a certain level - as would happen when all the TRVs are closed. If you do this, you then need some means of switching the boiler and pump on again when one or more TRVs open - for which you either need to keep the pump running all the time (stalled when all TRVs are closed) or you need to pulse it at regular intervals - so that the flow switch closes again and brings the boiler back on. You *might* have such a system - but I doubt it!

[John]

If you have the manual - or can find it on the internet, then you should be able to look at the wiring terminals and see if the room thermostat connections are bridged - or if they are connected to something somewhere.

[mick]

It shouldn't be a problem. If all rads have TRVs then there should be a bypass loop in the plumbing to allow some flow (sometimes this is a towel rail, without a TRV). The boiler shuts down pretty fast when the loop temperature climbs. The pump may cycle on & off (to sample the loop temperature) even though the burner doesn't run. If all TRVs on a loop are closed you *want* the hottest water to loop back. :-)

[gazz]

pretty similar to the set up in my rented bungalow, except i dont have TRV's!!!!!

not had to use the heating yet as we only moved in 3 weeks ago, but i can only imagine the system is relying on the water temperature stat to run the system, which as others have said is a very wastefull way of doing things,

I'm going to add a remote stat as soon as i find a decent priced one, i'm after one of the radio controlled ones, so i can take the stat into the bedroom on a night in winter and have the heating set at the temp i want when i sleep and have the temp reading from the room im using, then take it to the living room during the day,

It's just a matter of 2 wires to connect a remote stat to a combi, but you may need your landlords permision to do that, as it's an internal mod the the boiler i believe... which most will shit them selves and say you need to get a corgi to do the job, when it's just a case of removing the link wire, and connecting the stats wires,

[Andrew Holme]

Fit a wireless thermostat.

[John Stumbles]

I'm not familiar with these but you can have a look in the manual (which you should have) so see what it says about 'boiler interlock' and 'bypass'.

[John Stumbles]

It's also notifiable under Pratt P. Unlike, say, replacing an electric shower which is not.

[tim.....]

I thought that any work in a bathroom was.

tim

[John Stumbles]

Not like-for-like replacements