high or low pressure ball cock for big lof tank

[shooey]

Hi,

Wonder if someone could just answer a (hopefully) simple question for me.
I have two tanks in my loft (big one a and little one) and the ballock (valve) is playing up in the big tank and causing overflows.
It doesn't look like it will be too bad to just replace the entire ballcock, but they sell two different sorts in Wilco's - high and low pressure.
How do I know which I need?

Thanks

 

[JohnD]

it is fed from the water main, so you want a high-pressure one. The ones in the WC cistern, if they are fed from your tank, need low-pressure

the sort you need in the loft has the water outlet on the top, going across a sort of bridge, then squirting downwards.

preferably with a sort of polythene tube to prevent splashing noise.

you can usually alter valves from high pressure to low pressure if they come with both bits.

 

[shooey]

Thank you