New shower pump not working

[keh7486]

Hi I installed a new twin shower pump from gravity feed system
But when I turn shower on using the mixer the pump only kicks in for a few seconds then turns off. I know there's no air in the pump but could air be trapped else where cause this or is the pump faulty. This is the first time I've attempted any plumbing so any help would be appreciated.

 

[slapper]

Is the pump a negative or positive type, where is it situated?.

Did you use an Essex or Surrey flange for the Hot, where did you take the cold feed from?

 

[yerino]

I'd imagine you have air in your pipework.

Lower the shower head to the as low as you can get it turn on the shower to the middle of cold/hot and see it if can force the air out and water through.

 

[keh7486]

Thanks for the replays guys. I have narrowed it down to the shower head when I take it off the pump and flow are fine. Soon as you put it on the pump cuts out. Do you think I have bought the incorrect shower head

 

[kvsalamander]

It looks like you have a positive head shower pump that requires a natural flow of water to keep the flow switches lifted. It seems that when the shower head is attached, its slowing down that natural flow. My advice would be to either change the shower head to one that's not say, a mulitifunction or one with the rubber nodules on to a less restrictive one. The other option would be to fit a negative head pump.

regards