hot water cylinder stuck gate valve

[booyakka]

Hi, I shut the hot water off today with the gate valve that feeds the cylinder, changed the bath taps went to turn the gate valve back on and
nothing the red handle just keeps turning i think the spindle may be broken, so i thought just replace the gate valve only when i came to drain
the cylinder the drain off valve does not work i unscrewed the square nut fully and it looks like something has sheared off inside. Can someone please advise best, easiest method of draining down the cylinder so i can change the gate valve. I can drain the large header tank via the shower.
thanks in advance.
Alan

 

[seco services]

you don't need to drain the cylinder to change the gate valve.
turn on a hot tap that will drain the pipe.
why drain cylinder when gate valve is above it?
as for your drain tap you'll probably find the rubber washer has got stuck in the drain tap. which is common.

 

[ChrisR]

Remember there will be water in the pipe over/behind the gate valve.
Where IS the valve?

 

[wiggikins]

What you will need to do before changing gate valve is either empty the tank or stick a bung in the outlet!

Keith.

 

[kirkgas]

be careful, the position of the valve is critical whether you drain the tank or not, if the valve is not above the cylinder and you remove the valve you will get all the water in the cylinder coming back "up and out" of the bottom half of the cold feed pipe until the level in the cylinder is at the same height as the valve, if the valve is above the cylinder you will still get all the water between the tank and the valve coming out which can still make a mess

 

[hardbasta]

if u need to drain the cyclinder (drain offs never work) remove the top connection off the cylinder(wrap a sheet round to mop what spills) then drop a hose pipe in with a foot of copper stuck in it & syphon it out. (the copper stops the pipe curling in the cylinder)

 

[tonybhoy]

I usually just remove the broken spindle live.

Hardly any pressure there so you just need to be quick with a pair of pliers to pull it out then refit the valve sans spindle.

 

[hardbasta]

thats great, but you're nacked if the old 1 is fine threads

 

[kevplumb]

I usually just remove the broken spindle live.

Hardly any pressure there so you just need to be quick with a pair of pliers to pull it out then refit the valve sans spindle.

 

[tonybhoy]

thats great, but you're nacked if the old 1 is fine threads

Don't think you are following me.

I remove the gate and refit the top part of the valve (handle spindle etc)

 

[booyakka]

Remember there will be water in the pipe over/behind the gate valve.
Where IS the valve?

Hi Chris
the valve is about 3 inches above the bottom of the cylinder, i can drain the large header tank in the loft via the shower, i was wondering do you think if i blocked off the vent in the loft and closed all the hot water taps, then remove the gate valve would the water suspend itself,
cheers
Alan