Shower pump positive or negative head.

[Ansumstan]

Hi I am fitting a new thermostatic shower with a 2 bar shower pump. The pump will be on the airing cupboard floor about 2650mm below bottom of cold water tank. The shower head will be about 500mm below cold water tank. The pump will have dedicated supplies and a surrey flange fitted to the hot water cylinder. My question is will it be Ok to run the outlet pipes from the pump back up into the loft then across about 2 metres and back down 1.5m to the shower mixer and up 1m to the shower head? Ive not yet purchased pump but looking at the technical stuff for various makes on the net I appear to have positive head but would the pipes going into the loft effect that and make it negative head? Would the pipes to the shower need to be vented? if so how and where?
Hope this makes sense!
Stan

 

[Breesey]

To answer your questions in the order you asked:

Yes

No

No

Hope that's OK

 

[Ansumstan]

Nice one, Thanks very much for your help