Shower pump location

They prefer to push rather than pull. Next to the cylinder is ideal. However, you may be able to install under the bath, if you're lucky. Some things that will help if you intend to "pull":

1. Use a flange on the hot water cylinder to reduce possibility of air ingress.
2. Use flowed bends on the pipework, not elbows.
3. Turn the pump down. Should it be too high, the pressure drop on the inlet side may be very great (probably below atmospheric pressure), which can lead to cavitation and other nasties.
4. Ensure cold feed from loft tank to hot water cylinder is short, wide bored and has the minimum of valves (full bore, fully open) and elbows.

Note that this advice applies in all cases, it is just that when pulling, it becomes more critical.

The noise is similar in intensity to that of the shower water itself. You can always mount it on rubber and install soundproofing. It is a low hum and not particularly disturbing as a noise, even if you're close enough for it to be loud.

Christian.

Thanks Christian, that all makes sense.

-K