Aqualisa Shower Nightmare

[TheScullster]

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 The pump has been replaced by their service "engineer" but no change.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

[John Stumbles]

Does the flow of water change when it does this suggesting that it might be related to air entering the system? Does it screech continuously?

So the old pump also screeched in the same way? Does the sound seem to be coming from the pump unit itself? Doe sit change if you hold onto or waggle any of the pipes or the pump unit itself?

[TheScullster]

Thanks for response, John

Sometimes the effect is sufficient to reduce the flow massively. Mostly it's just an annoyance which scares the kids if it happens to them.

The screeching is intermittent and usually occurs once or twice for say a minute in a 10 minute shower. Yes, the old pump also screeched. The Aqualisa engineer replaced the pump almost on the off chance that it might be the cause. Turning the shower off for a few seconds and back on usually cures the screeching - temporarily at least.

I have also swapped the cartridge (incorporating the flow control and thermostat arrangement) thinking that maybe the stat was starving flow to the pump somehow.

I have yet to try taking off the cover and running the shower with the guts exposed. Being low voltage I guess this isn't too potentially hazardous. As the feed pipes are back entry, I'm not sure that "waggling" these will be possible.

Phil