Shut off valve not turning back on?

[Custom45]

Hi
I shut off the valve to my hot water cylinder to replace the immersion heater, however after doing that and turning everything back in there is no hit water flow. Mains cold us ok and the loft tank has refilled.

I'vw definitely turned the valve back on (between cold tank in loft and hot water cylinder). I'm wondering if it has broken inside and is now permanently off?

 

[CBW]

It is likely with the age of that gate valve. New one required me thinks.

 

[Custom45]

Trouble is, I think the pipe may be imperial.
Also, the cold storage tank above it is full, how do I empty it so I can safely take off this old valve?

 

[CBW]

Personally I wouldn’t, I’d bung it (tank outlet), a washing machine trap spigot (unused of course) has been ok for me once before, or syphon it out with a hose pipe, or bale it out up to you. If it’s imperial then you can get imperial olives, or use 22mm with plenty of ptfe tape.

 

[Custom45]

It's ok, looks it was just an airlock in the system, think it's cleared though.

Silly me, clever wife.