Optimum operating temperature of boiler

[Haveagohero]

Having just installed TRVs on my CH system, I have been wondering about how I get the best and most economical performance from the system.

Obviously fitting TRVs is a good way to make the rooms comfortable but I am thinking have I got the boiler set to it's optimal setting?. Its an Ideal Classic 55 an open vented system it also heats the water and for some wacky reason is setup so that the hot water is always being heated if the heating is on i.e you can not have it set to heat radiators only (although you can heat hot water only). Furthermore the radiator in the bathroom is always on if the water is being heated and apparently I must not put a TRV on that rad.

So all well and good, but what about the boiler setting? a knob numbered from zero/off to 6. Obviously this controls the temperature of the water as it leaves the boiler - I assume that's correct. But what should it be set at for optimal effciency and economy. It has always been set at 3 from the time it was installed 11 years ago and I was never given any kind of reason as to why 3 was chosen - probably because it was in the middle. The guy just said if it gets "real parky" I could turn it up a bit or if I want more hot water & quicker. But that hardly seems a great, well considered instruction.

[BLOD]

you could update your system so you can have independent control of hot water & of heating.
If you're lucky you may just need a new programmer to enable this, but if your not so lucky you could need a new programmer, new motorised valve and need to run some extra wiring.

[AWheating]

trial and error. Normally a lower number in the summer and a higher number in the winter is recommended as per manufacture instructions.

[Haveagohero]

you could update your system so you can have independent control of hot water & of heating.
If you're lucky you may just need a new programmer to enable this, but if your not so lucky you could need a new programmer, new motorised valve and need to run some extra wiring.

Thanks for your comments...

Any pointers on how I'd be able to check what I need?

Any comment regarding operating temperature setting?

[stevetheplumber]

start turning it down half a notch a day when your cold youve gone to far

[Haveagohero]

I didn't realise it was that basic / simple - makes me think I could have done without at least two TRVs!

[SimonJohns]

You can get a retrofit optimiser for the boiler

There's loads online. Clip on pipe thermostat and OAT. That will make it alot more efficient