No Pressure on new power shower

[Nekhul]

I have recently bought a Tavistock kinetic thermostatic mixer shower. This was replacing an old shower, running from a 2 Bar shower pump. Once installed, the pressure was very very minimal. The plumber said, its due to lack of power on the pump, as the new shower had considerably big heads. Well, I bought a Grundfos 4 bar pump, same plumber installed it. No change. Now he is saying that the shower may be faulty !!!!! Any suggestions ??? Please help......

 

[kbdiy]

Well you have in a rather expensive way concluded that there was nothing wrong with the pump you had so it must be down to the shower kit or a problem with the way it was installed. Presumably your old shower had good pressure on the original pump?

The sales blurb on your new shower says minimum 0.5 bar pressure required so you are well covered there. Could be a faulty unit I guess?

EDIT: just read the installation instructions and there are check valves and filters fitted in the supply. Perhaps not correctly assembled or blocked?

http://upload2.evocdn.co.uk/tavisto..._kinetic-and-logic-bar-valve-instructions.pdf