shower pump problem

[nabby68]

i have been doing some alterations to the pipework to my gravity fed pumped shower, just sank the pipework into the partition wall.
to do this i turned off both feeds via gate valves to my pump in the loft and after a few days of altering the pipework i have been turning the pump on and off and opening and shutting the gate valves on the supply to my pump after i found a leaky joint. i have now fixed the leaky joint opened both gate valves and turned on the elec supply to the pump but it doesnt work when i have opened the shower valve, also i dont get any water coming out of the shower???
could i have an airlock? and if so how do i get rid of this?
thanks

 

[Gasguru]

Never try running the pump unless the air has been bled from the pipework and pump. The ceramic bearings can overheat very quickly and melt the seals.

Remove the shower head and let the hose hang down.

If its a short pipe run you may be able to suck the water through.

Only run the pump once water free from air is observed.

 

[nabby68]

thanks gasguru
i have looked for a bleed screw on the pump but cant seem to lacate one any ideas?
and also, am i right in saying that the pump will not run unless there is water in it?
thanks