Where to turn off hot water supply in order to switch tap? All aspects of plumbing questions and answers, help, tips and information

[Reallee]

I need to change our kitchen sink and the taps too as a result. I can turn off the cold water no problem using the mains but am unable to turn off the hot water tap as there is no isolator valve, only a drain off valve.
Upstairs in the boiler cupboard (not combi) I think I have found the valve to turn off but just wanted to check I’m thinking the right thing?

I intend to;
turn off the boiler,
Turn off the cold water at the mains
Turn off the hot water at this valve
Drain the hot water tank
Remove taps
Add isolator valve
Replace taps
Turn mains water back on
Turn boiler on

Please are you able to tell me if I have missed a step or whether I am likely to create an air lock on the system this way.

Many thanks. Plumbers saying 3 weeks before they can help.

[stoneyboy]

Hi reallee,
Your sequence of actions is correct but you will only need to turn off the valve you have arrowed. This will stop cold water being fed into the HWT so you will only have to drain down the hot water in the pipe, the HWT will remain full of water.
Regards S

[Reallee]

It’s been a while since I tried to do this- life and covid meant I was held up completing this job. However I have gone back today, turned off water at the mains Ans then attempted to turn off hot water by and turning this valve and hot water has continued to flow freely. Can anyone advise what I should do to switch off the hot water?

[stoneyboy]

Hi reallee,
Yes it will continue to flow until the pipe work has drained down. If you have turned off the valves the hot water flow will diminish but it may take a minute or so.
Regards S

[Reallee]

Thanks I’ll give it another try