I am away for 2 weeks in January. I hope that the weather will turn milder, and when I go, I always turn my stopcock off in case there's a problem with the ball cock which once snapped and sent water thankfully down the overflow. However, in view of the current cold spell, should I leave the heating on low even though the water supply will be turned off. The house has cavity wall insulation, all pipes in the loft are well lagged and it is a mid terrace house.