Shower pumps- how many bar?

[argyle1]

I want to fit a pump to my Aqualisa thermo shower. Pumps come in different bar options: 1.5, 2.2 up to 3.5 etc. I have a large walk-in shower only, but would 2.2 provide sufficient water pressure to fill it? Any advice on this or good/bad products appreciated.

[Glencraig]

There's two sides to this one.
On the one hand, bigger is better so get the best you can afford.
On the other hand, how quickly do you want to empty your hot water tank. A 2 bar pump will make your shower run cold in half the time it would by gravity. A 3 bar pump would do it in 1/3 the time.
The choice is yours, but even a 2 bar pump will make a very noticeable difference to your shower.