New mixer shower

[cdw]

Hi - I have always had a mixer shower over the bath, which has worked perfectly, with no issues regarding flow or pressure. As the diverter had broken and the unit was old, I today had it replaced by a plumber. Now it would seem that the flow is reduced. The pressure seems fine when I use the mixer tap in the bath, but when I switch it to shower the flow is reduced. With my old one, the flow was ok but a little low when I had hot water only turned on, but when I added cold, this added substantially to the flow. It seems with this new one, there is no difference to the flow when I add more cold water - it stays exactly the same. Does anyone know what could be the problem? (It is a gravity fed system).

 

[kvsalamander]

Have you got gravity hot and cold or gravity hot and mains cold?

 

[cdw]

It is gravity both. The hot comes from the tank and the cold from a header tank in the attic

 

[leaks]

Maybe it's a fault with, diverter, hose, shower head, plumber.
Have you not asked him? Just a thought.

 

[kvsalamander]

is there any chance you could be running into negative head or close to the bottom of the cold water tank?

 

[ianmcd]

Have a look at the installation instructions for the shower, some have a moveable selector to select betwwen gravity or mains/combi and some you swap reducers depending on your system before fitting, as your last shower worked ok I would think you dont have a tank positioning problem

 

[cdw]

Thanks - there is nothing on the instructions regarding a choice between types of system. I did try a different hose, swapping for one with a larger bore and this has improved the flow. However, there is still no difference in the flow if I turn the tap on full or a little, or if I add loads of cold water, whereas with my previous shower it made a huge difference. If I turned both taps on fully it was quite powerful, whereas with this new one, it makes no difference to the flow whether I have just hot, or hot and cold, or taps on a little or taps on fully.