On 25 Jan 2007 15:57:56 -0800 someone who may be "wonderlander snipped-for-privacy@gmail.com" wrote this:-
The thermostat has numbers on them but they don't seem to correlate to
>the actual temperature, at the moment we have it set at 15 which is
>reasonably comfortable!?
Sounds like it is working well. 15C is a good actual temperature for a hall. Presumably you find the temperatures in other rooms about right? If so then it sounds like it is time to leave things as they are.