Gate Valves for High Pressure applications

[omegaman]

Is there a gate valve available on the market for use on high pressure/unvented systems? Reason I ask is I'm on site of 20+ flats that have unvented systems installed with gate valves as a means to isolate the how water supply from the cylinder and cold water just before it enters the cylinder. Naturally there is a mains screw down type stop cock.

These flats have bathroom and a shower room but there is only one H&C feed going to the bathroom which then tees off to the shower room and then to the kitchen. Surely there will be problems when all outlets are drawing hot water?

 

[Boilerman2]

I would use full flow Lever type valves, they have a positive shut off even at pressure and are not prone to leak

 

[Happyplumber]

I totally agree with the boilerman,i hardly ever buy gate valves now days all full bore lever valves

 

[Whitespirit66]

Gate valves were a nightmare. Control heads that fall off or are missing, and the valves seize if not used regularly.

As above, get yourself some full flow lever valves.

 

[tamz]

A gate valve will give full bore flow BUT should only be used on low pressure applications.

Better to use full flow lever ball valves as said.

 

[omegaman]

Thanks for the replies. So the general opinion is that it shouldn't be used but it won' cause any real problems (other than the spindle snapping off ). I won't be replacing them because the bosses have decided to use them and I can't do nothing about that.

What pipework arrangment (second part of my post)

 

[tamz]

These flats have bathroom and a shower room but there is only one H&C feed going to the bathroom which then tees off to the shower room and then to the kitchen. Surely there will be problems when all outlets are drawing hot water?

Depends on the sizing of the pipes. In a flat if 22 has been used it will not present a problem. Highly unlikely ALL taps would be drawing water at the same time.