Unbalanced supplies problem

[Nat]

Hi all,

Some advice/help please.

Fitted a thermostatic shower suitable for low pressure on what I thought was a balanced gravity fed system, teed into bath supply.

Turns out the cold supply is actually mains and so the shower is working properly when turned over to hot it just trickles out. There is enough head because when I use the shower mixer from the bath taps and hold it up to shower height the flow is OK.

The manufacturer says that the shower can handle of pressure differential of twice as which pressure on one side to the other. I reckon there's maybe 0.4 on the hot side and probably 2-3 on the cold. So there are a couple of options: reduce the cold pressure or put up the hot.

Has anyone tried putting a PRV onto the cold in a situation like this? I have found one that can reduce to 0.5 bar (£70!) and it would be a really easy job to cut it into the cold supply to the shower. Would this work?

Or I could fit a single impeller pump to the hot. Which brings me to another question: can I just cut the pump into the hot off the cylinder so I am in fact pumping all the hot draw offs to save running a separate supply to the shower and taking the floor up etc? Or is this going to draw in air from the open vent? Am I going to need to fit a flange?

Cheers

Nat

 

[SimonG]

Cold feed from tank. Needs to be done properly.

Always pays to check whats running from what.

 

[jtsplumbing]

Can you not just run a seperate cold supply from cold tank to shower ??

 

[Nat]

Can you not just run a seperate cold supply from cold tank to shower ??

I guess this would be a fairly straightforward solution although the loft hatch is about a foot square!

If the PRV option would work it'd probably work out roughly the same in terms of costs and be a lot easier. No one tried this?

 

[Titanium Trades]

PRV, neat, tidy and simple

 

[Millsy 82]

I tried a PRV once made a little bit of difference but the best way sort is to have cold feed coming from tank

 

[secret squirrel]

Of course you can take short cuts but the best option is to do it correctly. If you haven't got the money wait until you have.

 

[ecowarm]

Don't forget about back flow prevention

 

[tamz]

For 0.4 bar on the hot your shower head would be on the ground floor of a 2 storey house and tank in the loft.
If you are stuck and the cylinder is nearby take the cold from the cold feed to the cylinder. Not ideal but will work ok.

 

[kay-jay]

Take into consideration what the customer wants. Balancing the feeds is required but reducing the cold will result in a much poorer shower experience and pumping the hot will result in a better one........


Sent from my GT-I9100 using Tapatalk 2