shower pump not starting up

[muchtie]

I'm installing a shower on the first floor of my cottage. Cold Water tank is in loft above bathroom, directly above the shower, so not a lot of head
distance, about a foot. Hot water cylinder is in cupboard adjacent to shower.
I've bought a Stuart Turner Showermate Standard 1.8 bar Twin Positive Head Shower Pump and positioned it next to the cylinder,
feed via 22mm copper as per instructions.
Connected up to mixer, put in the fuse , BUT no water from shower head. I expected the pump to kick in as described in instructions,
but nothing. There is water at the mixer, but nothing past this point.
I'm probaly sure I should have got a negative head pump, amazing thing hindsight!

Can anyone advise.

Muchtie

 

[PlumbBobBob]

are there any isolators on the flexis on the pump. you don't need a negative head pump they are for the shower is above the cold tank i.e in loft conversion.

 

[PlumbBobBob]

is the shower fixed or can you remove it from it's holder. if you can put it down in the tray/bath and turn it on see if that starts it

 

[muchtie]

There are 2 isolators on the input side, but both are open. Shower head is not connected yet, just outlet on the ceiling of the shower ( open pipe). Definitely water in the pipes up to mixer and in feed to shower from the mixer.
Changed the fuse, checked the wiring, but pump not responding.

 

[Best]

Sounds like it's a bit borderline but would have thought it should work with little head. If you have an airlock, even though you maybe have short runs, the pump won't start as needs flow to start. By airlocks, I mean in any of the pipes but the ones leaving pump are more likely to airlock in your case I am guessing.

 

[PlumbBobBob]

just a thought, have you got a wet vac you could try pulling the flow through

 

[stani]

you need a negative pressure pump or a negative head kit. you need around 1metre head to get the pump to start.

 

[muchtie]

Haven't got a vac, but a strong pair of lips!! If I can get some water through the shower head feed is this likely to prime the pump for further operations. Howwould I check for airlocks, and how would I get rid of them. As you've probaly guessed I'm a novice in the dark art.

 

[stani]

if you have a magnet try runnig this over the top of the pump when its switched on this should kick the pump into action, it also tells you, a negative head is required.

 

[Best]

Haven't got a vac, but a strong pair of lips!! If I can get some water through the shower head feed is this likely to prime the pump for further operations. Howwould I check for airlocks, and how would I get rid of them. As you've probaly guessed I'm a novice in the dark art.

Don't be sucking the end of the shower feed pipe if the pump is ready to start! You could end up like a water balloon, if you survived! :yesnod: