Boiler thermostat - most effecient setting?

oldskoo1

Following the energy saving trusts recommendations for saving money on heating it suggests that its more efficient to turn up the thermostat on the boiler to max.

This i have done; the temperature control on the boiler itself that is; currently on setting 6.


However i'm confused - there is a white turn dial box above the boiler - just like a standard drayton white room thermostat (the ones that go from 0 - 30).

The one above the boiler only goes from 3 - 10 and is currently set on 3.

Any ideas what this is and what it should be set on?


Thanks!

Cardew

There are different types of thermostat.

The thermostat on the boiler itself(normally 1-6) controls the water temperature in the CH system. It can also control the temperature of the water in the HW tank if you don't have a tank stat.

Most boilers are more efficient the higher the water temperature - but it isn't by a great deal I believe - and many people(especially with young children) don't like the radiators that hot.

The 3-10 one above the boiler sounds like a frost stat. I have one in my 'outside' boiler room and is designed to switch on the boiler if the temperature in the boiler room gets cold enough for frost damage to occur, the 3 will be 3 degrees C.

oldskoo1

That makes perfect sense and HW tank has its own thermostat so turns off based on that reading i think.

Boiler is located at back of garage which explains the frost thermo you mentioned.


Thanks for clarifying!

Cardew

Yes the HW tank stat will stop the HW getting too hot.

I should qualify the "Most boilers are more efficient the higher the water temperature" comment. That generally applies to non condensing boilers.

I have read that doesn't apply to condensing boilers, but as mine is non condensing haven't bothered to read up on condensing boilers.