Fitting New Shower Cartridge

[Minatoar]

My shower temperature control doesn't work properly and I think I need to change the cartridge.
However, I cannot find isolating valves for either the hot or cold feeds.
As I have a combination boiler, can I simply close the mains stopcock?
Many thanks for any advice.

 

[Newboy]

Yes

 

[dilalio]

If you have a new suppliers plastic stopcock in the street and an old one inside the property, it's better to use the street one and, if your one is in bad shape - replace it at the same time as the shower cartridge.