My thermostat has been programmed but is running 24 hrs a day – is it faulty?

Probably not. The programme schedule will only operate if the system is on “Automatic” mode. Check if the system is on “Manual” mode – if so; press the “Mode” button on the thermostat until the “Automatic” mode shows (see the programming guide). Check the “Economy” temperature setting – if this is set to a similar temperature to the “Comfort” setting, this will have the effect of switching on the system 24 hrs per day.