ISOLTING HOT WATER TO CHANGE TAP

[DIYQueen]

I have been trying to isolate the hot water to the tap in the bathroom. I have located 2 gate valves in the airing cupboard and turned them off, but the water still flows from the tap. I wondered whether the valve was simply shutting off the supply to the hot tank from the cold, but when i run off water I can hear the cold tank refilling. I think I'm gonna have to turn off at the mains and drain both tanks, but dont want to do this if I'm missing something simpler.

[weareleeds]

Follow the 22mm pipe down from tank to the cylinder the gate valve should be on this pipe if you have already turned this one off then it is likely to be sheared off inside (very common)