jim8flog
Journeyman Pro
re your edit YesMy combi is in the loft, so switching preheat on and off based on requirements isn't a practical option.
And of course leaving preheat on permanently is way more wasteful than having a well insulated hot water tank.
EDIT: we seem to have come a long way from discussing EVs!
I cannot understand boilers being put in lofts unless the boiler is in a fully insulated cabinet.
What they call a frost thermostat is a bit of a misnomer. I know my boiler kicks in automatically if the temperature drops
to 8 deg C.
My neighbour had their's put in to the garage and it was firing up 24 hours a day in the colder periods. It was second home at the time for them and they never realised.