Gate Valve Problem

[planemad]

Hi All

I'm fitting a kitchen so had to change taps, the old pipe work near the taps has no iso valves so I had to isolate the hot water from the tank cupboard using a 22mm gate valve that comes up from a pipe that comes out of the bottom of the immersion tank and travels directly up to the loft.

The gate valve has snapped closed so it just spins freely now still blocking off the water.

What do I have to drain down to change this compression gate valve?

Many Thanks

 

[Terry lambert]

You could bung the pipe in the cold water tank, open the hot water tap until water stops running. If the valve is above the height of the cylinder you can now change the valve ( maybe full bore lever valve would be better)

If your gate valve is below the level of the cylinder, you will have to put a hose on the drain cock at the bottom and drain to at least this point and then as above.

To be safer you could turn off the main and then drain the cold tank and hot tank to the level of the gate valve.

 

[dcawkwell]

Bung the cold tank and open the hot tap.
The will be a quantity of water in the feed pipe when you remove the
gate valve.

 

[planemad]

Thanks - can the cold water tank be drained from the drain cock on the bottom of the hot water cylinder.
Also the gate valve is just above the level of the hot water tank so maybe I will not have to drain the whole hot water tank just the tank in the loft??

 

[dcawkwell]

Thanks - can the cold water tank be drained from the drain cock on the bottom of the hot water cylinder.
Also the gate valve is just above the level of the hot water tank so maybe I will not have to drain the whole hot water tank just the tank in the loft??

Water in the hot tank isn't a problem, water doesn't go up. It the cold water above.