Positive head shower pump

[Yezzip]

I have fitted a 1.5 bar positive head shower pump .it is fed by cold water tank and teed off hot water from cylinder.the pump is fitted on floor in cupboard next to cylinder. The shower head is 400 mm below cold water tank.the problem is the pump will not kick and work.Is this due to lack of flow from tank ? Or do indeed a negative head pump? Any help will be invaluable !

 

[steve32]

If the pipe work to the shower valve goes up and over in the loft then yes you will need a negative head pump.

 

[Yezzip]

Hi Steve thanks for reply but pipe work to valve comes from tank in loft down to pump in cupboard next to hot water cylinder then from pump up roughly500mm to valve

 

[steve32]

Are there any non return valves fitted in the shower valve, they are fitted in some valves by the manufacturers.
If they are fitted they should be removed by the installer for pumped or gravity systems.

 

[shray]

Are we talking twin impeller shower pump here ? Have you purged the water through correctly ? Try disconnecting the shower hose from the bar mixer and turning the pump on and off from the switch a couple of times.