Re: Smart heating systems do have their uses. @AC
Duh! Every bog standard mechanical room stat has a little snowflake legend printed on the low end of the dial.
If you're going away, set the heating to be on 24hrs a day and turn the dial to the snowflake. Your heating will come on at 6°C and stop the pipes from freezing. It will turn off when the house is a few of degrees warmer.