Running gas heating and hot water together?

Glum

Without going too far off-topic, I think it is generally accepted that a very warm bedroom is unhealthy. As long as your body is warm, you should sleep better. We have not evolved since central heating was invented.

As to the question of letting the house cool down overnight, there is a lot of fuzzy information out there but insulation is a key factor. Others may helpfully direct you to the science and whether you get something for nothing.

Reed_Richards

max1000000 said:

For example, if the temperature is 4 degrees overnight, is it better to drop the thermostat to, say, 16 degrees or to 13 degrees before raising it to 21 degrees in the morning? 13 to 21 is a lot more heating than 16 to 21.

You're imagining the the temperature inside your house will drop to the set temperature on the thermostat.  Unless your house is very badly insulated and/or very draught that's not going to happen.  You would have to lose a degree an hour to get the temperature down from 21 C to 13 C in 8 hours overnight.  My house would lose only about 3 degrees in that time.

Alnat1

For many of us who use these forums, heating goes off 30 minutes before bedtime, on 30 minutes before you get up. Heating off while you're out during the day, unless only out for an hour or so.

I heat to 16C in the mornings because I'm generally busy doing something. As temp drops later in the day I'll heat to 18C if I'm not active. Heated throw for evenings rather than thermostat up higher. TRVs on radiators, set at 1 (10C-ish) in unused rooms, 2.5 (16C-ish) in bedroom/kitchen, max in living room (where thermostat is) Doors kept closed between rooms when possible.

Heating not been on yet except to test it was working ok, although it will come on automatically if temp drops below 16C in the day now. Came close this morning, living room was down at 16C first thing, expecting it to click on one morning soon.