Replacing hot water w/m check valve

[stevemcevoy07]

Hi I have recently moved into a new house. I have just got a new washine machine which only runs on a cold water supply and have noticed that the hot water check valve under the sink is dripping ever so slightly. I have bought a new check valve(Straight 15mm x 3/4" BSP) to replace the old one.

My question is this, if I turn of the water mains supply to the flat and drain the water by running the taps. This should effectively let me change the hot water valve and not flood the kitchen. But I have a combi boiler and every time the hot water tap is run is kicks into action to heat the water. I am concerned that I might damage the boiler or even not drain the water supply.

How do I go about draining the hot water supply so that I change the check valve without flooding the kitchen?

 

[ChrisR]

Turn the combi off first

If you can get at it you'll see a tap on the CW inlet to the combi. If you turn that 1/4 turn to off, nothing much will come out oif the washing machine HW tap. If you open say the kitchen hot tap, the pipe will empty out of the WM tap.

Or you can turn the property's whole supply off.

 

[stevemcevoy07]

Thanks ChrisR, will try that later today.

 

[stevemcevoy07]

Hi Sorry to ask again, I have a Saunier Duval THELIA 23, I have found the CW inlet, but cant seem to budge it. I have not really went for it as I dont want to damage it. Are these things pretty sturdy before I go for it.

I have never had anything to do with boilers EVER and unsure of the build quality of them.

Sorry to ask probably a stupid question, but better safe than standing in a floor of water