My brother will be away from home due to health issues for up to 9 months. To stop water freezing in the pipes I tried to turn it off. Eventually located the stop cock down a hole in the front garden, next to the water meter. Turned it off which stopped the cold water , but hot water carried on flowing as usual when hot tap turned on. His heating and hot water system is an old hot air system and there’s a water tank in the loft. Any suggestions for getting the hot water turned off too gratefully received. Thank you.