"BillR" wrote in message
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Bob Mannix wrote:
"PM" wrote in message
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"Bob Mannix" wrote in message
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snip

I fear that, if it's a gas tap that someone used for water, the
water will make it prone to complete seizure. I have not seen a
water tap like this, you might be advised to consider changing it.
Mind you, the cheap gate valves always stick (as another poster
said). The only real way round this is to shut and open them every
6 months, except you never remember :-(

Washing machine valve?

Pete


I know that was a little tongue in cheek, but a serious response is
that the (only?) advantage of gate valves is that they are full
(22mm) bore as they only deal with the hydrostatic head from the
header tank. Washing machine valves, which may have to withstand
mains pressure, are not full-bore (in terms of the 22mm pipes they
would be isolating) and would severely restrict the flow.

I've got gate valves on my CH pump.
They have been there 25 years and pump has been changed 3 times without a
problem with the valves.
Mind you I never leave any stopcock or valve so its hard open, just keep
them a fraction of a turn from the fully open position.


I replaced my cold water tank two years ago, within a year one of the gate
valves wouldn't shut off :-(