Salamander pump & mixer shower - not starting up first time

[a4drk]

Hello
I'm only qualified 11 months in plumbing.
Its things like this where I'm lacking in experience :


I installed a Salamander pump & a Bristan mixer shower to a customers house.
They just had a bath only in their bathroom on the 2nd floor. (Existing Shower room on the ground floor - with a pump / mixer shower)

They wanted me to fit a mixer shower & a pump.
So, I Tee'd the hot & cold off the bath taps (22mm) & ran 22mm pipes to a Salamander pump. (RSP75)
(output to the shower was 15mm)

When the customer turns the shower on - nothing happens.
It can take 5 or 6 turns on & off before the pump kicks in - then it runs fine.
(When I installed it & tested it - it all work fine - started up immediately)

Its a 2 storey house + an attic above.
The CWSC is in the attic & the Hot Water Storage is on the same floor as the pump / bath (2nd floor)

Is this a flow problem ?
or should have I installed a negative head pump.

any help much appreciated.

Cheers
David

 

[PlumbBobBob]

shouldn't really have teed into the bath feeds, shower pumps should always have their own dedicated feeds from the hot cylinder and cwst. also the pump should be situated at the base of the hot cylinder not under the bath.

 

[dancinplumba]

did you read the pump MI's ??

 

[REDSAW]

sounds like the shower feed supply is drawing very slightly to the kitchen when the hot supplies are being used there inhibiting the flow switch to be activated.
this will burn out the pump rotors and invalidate the warranty as in the m.i.

does the hot feed pipe fall into the pump or is the pump drawing the water?.
it worked when you installed it because you primed the shower!!

 

[a4drk]

Thanks for the input guys.

I fitted single check valves to the "exit" pipes to the shower (Hot & cold)
Surely this wouldnt affect it ?

I think I'll re-plumb it - by disconnecting the bath taps & run it straight to the shower.
If that cures it - I'll need to run new pipes from the tanks.

The Hot storage tank is only about 3 feet way in a cupboard (same level)

David

 

[Mike Jackson]

The single check valves may reduce the flow rate to the point where it struggles to actuate the pump.

 

[a4drk]

Cheers Mike.
I'm going to replace the check valves with straight couplings.
Hopefully this might do it. - If not, I'll need to re-plumb it.
I'll keep u posted
Cheers
David

 

[SimonG]

and check the filters, could have picked up some debris.

 

[a4drk]

SORTED !!

It was the check valves that was the problem.
They wouldnt even open when I blew through them.

I replaced them with 2 straight couplings.

I know now for future !
Thanks for all the input.

Cheers
David