18c is freezing for us, mine is set to 20c from 7.30am till10am, then 21.5c to 7pm and 22.5 from 7pm till 9pm, overnight is 19c.
House is mid terrace with no wall insulation.
Everyone's heat tolerance is different and i know people who boil when temp hits 17c in the sun, whilst for me 24c in...