Concealed shower valve connected wrong way round

[forgottenlife]

Cut it from the boiler room side and put an access panel back

Thanks, will try to do that at the weekend and see how it goes, fingers crossed!

 

[forgottenlife]

Thanks for all your advice. It turns out the two pipes in the boiler room shown in the photo feed directly into the shower only. I switched them round, and all is now working perfect. Cheers!