The message et
from "Dave Liquorice" contains these words:

I'd say your nighttime setback to 18c isn't enough. Many would find
unnecessarily high when in bed. 15 would be more normal - and a well
insulated house probably won't drop this low anyway even with the
heating off.

Our living room very very rarely gets below 15C and that has 3 external
walls solid stone walls and we are high and exposed. Heat loss is high by
modern standards.

The programable stat is set to 18.5C day, 20C evening and 15C (I think)
night but we actually turn the heating off at night otherwise the creaks
and bangs wakes us up. If you're wondering how I know that the temp in the
living room rarely gets below 15C the AWS base station is in there and it
records the internal temp.

I am in a lower (535 feet ASL) and probably more sheltered situation
than Dave but likewise have a poorly insulated house with 2 foot thick
stone walls. I have also had a weather station since early March so I
thought I would see what that said about my living room temperature. I
don't yet have a winter record but the house seems to get marginally
colder than Dave's when it is cold outside.

March and the early part of April dropped to about 14C overnight on a
fairly consistant basis. On 21st - 23rd March when I was away and the
heating was in protection mode for 2 days the temperature dropped from
17C to 8C and the 2 following nights dropped to 12C and 13C before the
house warmed through again. And at the tail end of last month the
temperature dipped to 13.5C one night so I expect that if we have a cold
winter the heating will often be coming on overnight when the thermostat
switches at 13C. Luckily I have mains gas so I don't suffer financially
quite as much as Dave on oil.

18.5C during the day can be a bit "cool" if the wind is blowing and it's
near or below freezing outside. With elderly, not very active, people it
is very easy to get rather too cold just sat in a chair and not notice it.
20C day is about right, 18C in a bedroom I'd find stifling 15C would be
better but then I'm relatively young with good circulation.

It might best to go with how you feel, if you feel cold or get cold sat in
a sensible amount of clothing then the room needs to be warmer. Use the
actual temperatures as a guide rather than an absolute it *must* be
22.167892C.

I have the house set to 17C during the day which can feel a bit chilly
when sitting around but warm when I get round to the occasional bit of
housework and overpoweringly hot when I come in after being active
outside so I agree with Dave that feel is the key. Old people (Mary
Fisher excepted) need an envirionment several degrees higher than what
typical youngsters find comfortable.

--
Roger Chapman