Thermostat temperature???

penrhyn

Mae is conspicuous by her silence, perhaps she melted.

mae

Thanks for all your replys I'm gonna read through all the posts properly and try and live with a lower temperature. All my radiators have settings on them too so gonna look at changing them. For some reason my living room radiator is always the coldest in the house if though it is set on the highest???

MATH

Ours is set at 18 in the day and turned up to 19-20 for watching TV in the evening. We have TRV's fitted to all but two rads so these often switch off before the room stat.

TRV's turn off individual rads but do not communicate with the boiler. All the rads may have turned off but your boiler will keep heating up the water because it doesn't know hot water is NOT require until the room stat tells it by switching off. This is why you should keep the room stat and leave the rad nearest it without a TRV. HTH

jennifernil

Actually, that is NOT correct. When/if all the TRVs shut down the temperature of the water returning to the boiler increases so the boiler's own thermostat will turn it off. The pump keeps circulating the water and when the water temperature drops sufficiently the boiler will start up again. This is how TRVs are supposed to operate
Newer boilers are fitted with a by-pass so the water can still circulate freely, otherwise disaster would ensue. But it is still a good idea to have one radiator that cannot be shut off. In our system we have one radiator in the hall that acts as the by-pass and has no TRV.
We fitted TRVs in our previous house in 1975, so it is not exactly new technology.
It would seem that room stats are now being fitted to switch off the pump too, so in my opinion this is interfering with the correct operation of the TRVs. As I said, personally I would disconnect the room stat, but then I am only a mere housewife!!!!

djohn2002uk

Almost 100% jenifernil.
But our system (Y Plan) has TRVs on all radiators and there is no need for one without because a bypass is "built in" to the pipework.
This to me is the most efficient type of system as long as the whole system is balanced correctly.
Using one radiator to act as a bypass would mean a considerable loss of heat through that radiator and would keep the boiler running a lot longer.

djohn2002uk

albertross wrote:

If there was no overriding room thermostat, the boiler would kick on and off all day (depending on timer settings), and the pump would die a lot earlier.

Well our system has been running like that for over 25yrs and the same boiler and 3rd pump. And I'm pretty sure British Gas changed one of those unnessarily whilst trying to eliminate a fault.

With the Y Plan, which is very common, the nearest room to the boiler doesn't come into the equation. The water is pumped to one or two manifolds, each of which feeds 5 or 6 radiators at the same time. The nearest to the manifolds will tend to start heating up first but not at the expense of the others. It just takes a little longer for the hot water to reach them. So, the nearest feels "warm" sooner but by the time that one gets really hot the others are hot too.

djohn2002uk

albertross wrote:

Maybe you'd still be on your first pump if you didn't run it like that.. It is commonsense that it won't last as long, and is wasting electricity if it is on all the time, when it doesn't need to be. It is also wasting gas. Try it for a month to see if your bills go down.

I can't try it for a month. Y Plan doesn't have a room stat.
And effectively 2 pumps in over 25 years is good enough for me.
And at just over £30/month for gas, heating and cooking, I think I'd struggle to save much more.

bunking_off

I don't think anyone would dispute that it's perfectly possible to have a system without a room stat, as described by Jenifer and djohn. The point is that it doesn't comply with Part L1 of the building regs/best practise. That doesn't mean that anyone with such a system should go ripping it out or amending it to comply. It does, however, mean that the advice to Mae to take a system that is compliant and make it non-compliant by disconnecting the room stat is dodgy.

Personally, although I have TRVs on all my radiators except the one near the room stat (as per best practise guidelines; well it's a new build), I'm glad I have the room stat because I find TRVs lack precision. Also, as I say, I have my system configured to change temperature during the day, which (I don't believe) can be done automatically with TRVs.

[Deleted User]

TVRs on all but the 4 bathroom rads and one airing cupboard rad. Bathroom rads are turned down at the valves. All rads warm but some ie living room warmer than others. No central stat but a stat on the condensing combi boiler, which is turned to the lower of the suggested temp range. Result = nice temps at min energy cost. I don`t like the house too warm and I turned the timer off at 7am today as the house was warm

New build, good insulation and a frost stat on the boiler. I don`t think I could do better re energy costs: comfort

(too many loos by the way!!!)

Cardew

bunking_off wrote:

I don't think anyone would dispute that it's perfectly possible to have a system without a room stat, as described by Jenifer and djohn. The point is that it doesn't comply with Part L1 of the building regs/best practise. That doesn't mean that anyone with such a system should go ripping it out or amending it to comply. It does, however, mean that the advice to Mae to take a system that is compliant and make it non-compliant by disconnecting the room stat is dodgy.

Personally, although I have TRVs on all my radiators except the one near the room stat (as per best practise guidelines; well it's a new build), I'm glad I have the room stat because I find TRVs lack precision. Also, as I say, I have my system configured to change temperature during the day, which (I don't believe) can be done automatically with TRVs.

Instead of disconnecting the room stat, you could simply turn it up.

I wonder if the point made in another post about pumps 'wearing out' because they are running longer is valid. Frequent stop/start operation often causes more problems for mechanical devices like pumps than constant running.

Whilst pumps obviously consume power when running they are typically rated at around 60 watts. So if even if they run for an extra 5 hours per day the cost will be approx 2p.