Shower booster pump installation (boost all outlets)

[Retreat]

hi, have a indirect hot water cylinder with hot and cold both fed from a 80 gallon cold water tank.

Have recently fitted a thermostatic bath shower mixer tap as didn't want to chase walls/remove tiles to fit a dedicated shower. Both has poor flow plus the flow to basin tap is generally poor which I'm guessing is due to a gravity fed system.

Planning on fitting a salamander 2bar twin negative head booster pump in airing cupboard.

I want it to boost all outlets in my house.

Would it be ok to fit a Surrey flange on the hot and run 22mm to pump as the hot suppy l, and where the old hot draw off on top of the cylinder tees off for the hot supplies cap that part of then connect the outlet of the boosted hot back into the hot water circuit?

For the cold it is ok the find the cold down services from the cold water tank cut into it and fit an elbow into the pump and again fit the boosted cold back into the other side of the cold pipework? Wouldn't have thought I'd need a dedicated suppy as I'm boosting all outlets and not just the shower?

Do I need to fit non return valves on the other side of the pump or will they all ready be built into the pump?

And finally, is it worth fitting a AAV on the inlet to both hot and cold supplies feeding pump to help with any air issues?

Thanks in advance for your help/advice.

My skill set for plumbing is pretty good, so far I've fitted my own bathroom and replaced hot water cylinder in my old house.
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[Unregistered]

Bump!

 

[Ray Stafford]

Oh blimey. Where to start?

Shower pumps are probably the most often cocked up of all installations, even when done by professionals.

Make sure that you have a whole house pump if you want to pump all outlets. If you use an ordinary shower pump, it will get very stressed when someone opens just one tap (say cold only) and leaves it running, as the hot side impeller will be running against a closed head - a recipe for overheating and blowing out the seals.

This raises a fresh problem - negative head pumps tend not to like whole house installations. In particular, WC fill valves can confuse their pressure sensors, so be prepared to replace them (the cistern valves) with equilibrium valves.

Finally, I strongly recommend drawing out what you are planning, and sending it to Salamander tech for approval. The layout of pipework around the pump can create plenty of problems!

Good luck. Or better still get a good plumber in. Not any plumber, and definitely not a builder who "does a bit of plumbing".

 

[thompsonbrown]

A few good points made above so just to add, you could consider a universal pump and your bathroom should have cold mains to your bathroom basin if it has it may also feed your Wc's.

 

[plumbersm8]

The Salamander ESP75 (2.0 Bar) and CTforce20tu (2.0 Bar) are both suitable for a whole house negative head system. You can use an S Flange if you have more than 1.2m between the base of the cold water tank and the top of the hot water cylinder, if not then you will need to use a non-stop Essex flange (pump best sited at base of hot cylinder) The side connection of the S Flange needs to go directly down to the hot side of the pump, the cold supply from the tank needs to be dedicated also. you can cap the feed from the open vet to the existing services and from the pump connect back into those supplies. I agree with Rays comments regarding the toilet, as the Negative head pumps activate on a pressure drop, when the ball valve closes after the toilet has been flushed- the movement of the ball valve 'bobbing' up and down can trick the pump into thinking there is a demand. Fitting Equilibrium valves should resolve this issue. There is no need to fit NRV after the pump as they are integral to both pumps, you can fit AAV to highest points after the pump before it drops down to the shower. I would try emailing Salamander directly or ring their technical team if you need more help installing the pumps- hope this helps!

 

[BLOD]

If possible try not to pump the wc - even the quietest pumps can sound noisey in the middle of the night after you've had a pee.