Our thermostat is on the upstairs landing (which I think is a silly place to put it) but it generally gets set around 21 deg. at this time of year. However since mom developed Alzheimers over the summer, her hands always feel icy which I guess is due to her illness. I turn the thermostat down to 17 deg. when we go to bed so, at the moment, it seems to click on around 3am., although if I get up for the loo around 5, I then turn it up a little more. Me, on the other hand, since going post menopausal seem to carry my own personal radiator around with me so I regularly get a dab on.