I live in a bungalow consequently a small head on the recently installed
thermostatic shower unit. I'm only getting a trickle so I want to boost the
pressure a little, nothing fancy like a 3.5 bar multiple shower unit, just a
small boost. The base of the roof header tank is approx 600mm above the
shower head, the minimum head recommended for the thermostatic unit is 0.1
bar which I assume is approx 1000mm.
I cannot seem to find a shower giving less than 1.3 bar, my main concerns
are :
1 Reliability.
2 long life.
3 high ambient temperature ( installation in Airing cupboard).
4 Continuous rating.

Would the inclusion of valved bypasses from inlets to outlets reduce the
strain on the pump by lowering the outlet pressure, or would the consequent
increased volume through the pump be detrimental to reliability.
Any thoughts and/or recommendations as to which pump I should buy.

I'm inclined towards :
http://www.screwfix.com/app/sfd/cat/...83326&ts=32744

or:
http://www.screwfix.com/app/sfd/cat/...20 7&ts=34457

What does the team think?

Regards
Don