good advice, but can backfire.
I used to live in a tiny flat. The main room had a kitchen counter along one end with a cooker in the middle, so on winter evenings I'd cook my dinner, turn off the oven, and leave the oven door open. Combined with the thick heavy floor-length curtains covering the room's single window, this would keep the rest of the room snug until I went to bed.

Until the evening when, a couple of hours after dinner I realised that I had an awful headache and was rather uncomfortably warm... yep, I'd forgotten to turn the oven off. For about two hours it had been valiantly trying to heat the whole room to 220C (or Gas Mark 7). This was reflected in my next energy bill. Ouch.
( Batsgirl, Sat 12 Nov 2011, 21:40, Reply)