Plumbing Question

Single shower impelled - hot water only coming out of small shower head, not big shower head


We have installed a thermostatic shower rail to our shower room. The shower rail has a big shower head (which is fixed to the wall) and there is a small shower hose.

We have fitted a positive shower pump to the hot feed. There is good hot pressure to the small shower head, but no hot water comes out of the big head. I have also put the small shower head to the level of where the big shower head is, and hot water still comes out.

If I turn the thermostat to cold, then the cold water comes out from either the big or small shower head.

This is in an ex council flat. The cold water tank is fixed to the wall at the highest point in the kitchen (hidden in a kitchen cupboard!).

Someone has suggested that we may have the wrong pump and should have gone for negative. What I don't understand is why the hot water is activated with the small shower head, but not with the big shower head.

Is there a possibility that there is a fault with the shower (air lock or even a faulty lock)?.

Lastly to switch from the small to the big shower head, I need to turn the left inside valve (clockwise for big and anti for small).

Any suggestions would be greatly appreciated!


3 Answers

Best Answer

View the link below, it will assist you in identifying whether you have the correct type pump installed, the link is to a UK shower pump manufacturer. (You will need Adobe Reader installed to view it)

copy & paste above url into your web browser

Answered 27th Apr 2013

Boiler Homecare

Member since 6 Jan 2010

It will still be classed as negative head, even though you lift to rain head height the outlet for the hand held is still down low, what happens when you start on hand held then switch to rain head? If nothing still, I would say faulty diverter for your new set up, just a process of elimination. Hope that helps

Answered 20th Feb 2014

MapleLeaf Plumbing & Tiling

Member since 4 Dec 2008

The simple answer to this is that if it is incorrectly installed, get a qualified plumber to fix!

Answered 29th Apr 2013


Member since 20 Feb 2010

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