Shower problem

[Keith Self]

Hi I had a shower fitted by a so called plumber that I found on a recommendation site. For 8 weeks I had water flowing over my bathroom floor from leaks from his work. I still have problems but will not have him back in the house. The problem now is the pump (hot water only)will not start because of the cold water pressure, I have a pressure  reducer fitted to the mains fed cold water. When the shower is turned on often the cold flows but no pump works until you turn cold pressure valve off and soon as pump starts you can then turn up the cold feed and it works fine.
I am not a plumber but could have done a better job and £500.00 cheaper. I was wondering if I need to fit a non Return valve to the hot supply between shower and pump to stop any cold water back tracking into the hot pipe and building pressure and stopping the pump.
 If there is a proper plumber out there who can give advise that would be great. Any help. Thanks kas

 

[Andy™]

sounds like your hot water is fed from a tank and he's fitted a pump on the hot but not the cold? thats wrong, your supposed to pump both hot & cold for this very reason... fitting a non return valve wont help, the pump only starts when there is water flowing

 

[Geoff1946]

It all depends what sort of Hot/cold supply system you have. Most shower pumps cannot be connected to the water supply directly, only to a tank supply, and the two pressures must be similar.

Incidentally, by the sound of his plumbing expertise I would be concerned about what he has done for the electrics!

 

[OnOff]

What system do you have, combi boiler or a big cold water storage tank in the loft and a copper cylinder in the airing cupboard etc?

My shower is pumped. Pump gets fed from cold water storage tank one side and hot cylinder the other. There's a flow switch on my cold side only. To get the pump to kick in I have to drop the handset to the shower floor. That's a head height problem.

What model of pump do you have?

 

[SPECIAL LOCATION]

Get hold of a copy of the installation instructions for your shower have a look at what they recommend for the plumbing arrangements..

I would be betting they do not say use a single pump..

More likely one of the numerous twin pumps available..

https://www.screwfix.com/c/bathrooms-kitchens/shower-pumps/cat820270#category=cat820270&page_size=100

Basic rule-of-thumb..

If you have two pipes feeding the shower, you want a twin pump fed from a pair of tanks that are pretty much equal in volume and height to maximise you chances of a near balanced supply coming in..

{OR..  a pair of pipes from a combi boiler both flowing at incoming street pressure.}

If supply is not balanced you are opening yourself up to no end of problems..

I would think it will be quicker overall to start again with the plumbing ?

:coffee