My by pass valve has a leak

Hi i seem to have a lot of noise coming from my boiler mate.
I noticed that my pressure gauge had dropped to zero which i then opened the filling loop back up to 1.5 bar.
I then heard a drip from the bypass valve at the red end which only stopped when the pressure gauge went back to zero.
Do i need to just replace the by pass valve? if so do i have to fit a gledhill one or can and 22mm angled bypass valve work as there is about £70 difference.

Many thanks for having a read.

if the aftermarket valve has the same rating and fitting, yes go for it. some parts on the Gledhill are only standard of the shelf parts and there is not always a need of Gledhill soled parts as replacement.( and of course £70 is a big different and better in your pocket as in Gledhill's)
Hope this helps

Mario at Mario's Boiler Service