Boiler ON OR OFF?

NiNjA

Huge thanks to you guys for your help. This is the first time I've used the forum, and it's been a huge help.
I think that the recent price rises and cold snap are to blame, but I'm now looking at perhaps turning off the radiators that I don't really need (spare bedroom/bathroom etc) as I think that could also help to reduce costs - thoughts?

Meanwhile, extra layers of clothes and plenty time out on the push bike I think

victor2

Rather than turn radiators in little used areas off, just turn them right down. Do they have their own Thermostatic Radiator Valves which can be set to anti-frost? Also, if you have a main thermostat for the heating, what is that set to? If the system is timer controlled, use that to only have the heating/hot water running at a suitable time.
Presumably you have a hot water tank. Is it well insulated? If not, insulation jackets are cheap and pretty easy to fit.
Do you have a loft and is it well insulated? Again, usually inexpensive to improve.

NiNjA

They've only got an on and off option. The main thermostat for the house heating changes, depending on the time of day. Whilst I'm at home in the day (not working at the moment) the heating is off, regardless of the temp outside, then about dinner time, I allow the heating (up to 20 degrees max) for an hour or two, then when I go to bed, it's always switched to below 15.
The loft is insulated and the tank too, thank goodness!

victor2

Is your hot water in a gravity system where the water is heated whenever the heating is on? If so, you would never need to have separate hot water running at this time of year.
If your radiators don't have TRVs, they presumably have a valve that you can turn right down, not just ON or OFF?
At night, even with the thermostat turned down to 15, the boiler may be firing every now and then to maintain water temperature, even if the central heating pump isn't distributing it - particularly if you have a gravity hot water system. Better to have both hot water and central heating completely off at night. Do you have a timer control you can do that with?

analyst_2

A little addition for anyone else who looks up this thread.

On Thermostatic Radiator Valves (TRV's) please note, these things are very prone to sticking if left in the same position for long periods of time. Internally, there is only a small pin which gets pushed in and out of a small orifice. Oh, am I allowed to use the word orifice in here?

So you ought to quite regularly crank the TRV right in and out a few times to make sure it it running free and doubly so if you've left the system off and stagnating over the summer months.

macman

You really don't need the heating on all night at all, unless you are elderly or have a medical condition.

unclebulgaria

I don't deny that turning a boiler off altogether is obviously cheaper than keeping it on low but, intermittent heating adds 10% to the sizing calculations for a boiler so turning heating off must add something to the running costs somewhere.
Just to add, why not test the theory yourself OP? Turn your heating onto constant for a week using the room thermostat to control the house temp, set it at 19 deg and drop it at night or when you go out to 10 deg. Then the following week set it with the timer at the same temps. Check your meter readings each week and compare them then get back to us?

macman

The only problem with that method of testing is that it assumes that the ambient outside temp is exactly the same for both trial periods. It'll give an idea (to which we already all know the answer). but it's not a calibrated test.

Cardew

macman wrote: »

The only problem with that method of testing is that it assumes that the ambient outside temp is exactly the same for both trial periods. It'll give an idea (to which we already all know the answer). but it's not a calibrated test.

Exactly - we already know the answer.

Accurately quantifying the savings is virtually impossible.

analyst_2

But with time the method will get more accurate.
So come back here and report your results in 10 years and then again in 20 years.

Go on, be a good sport.