I have an Aqualisa Aquastream power shower which has given constant grief!
This is the type which uses gravity feed hot and cold water with a low
voltage accelerator pump in the shower unit.
It's latest trick is to screech loudly after a few minutes use.
The pump has been replaced by their service "engineer" but no change.
He claims that there is too much air entrained in the water coming from the
cylinder and that I should re-plumb the take offs for this into the hot
water tank wall.
But the shower has only started making this noise after 2 year's use!
Yes I've made alterations to the hot water plumbing, but not to the pipe
runs feeding this shower.

The only saving grace is that Aqualisa support has been generally of a high
standard.

Anyone got any ideas on the shower noise please?

TIA

Phil