Aqualisa quartz 8.5 low hot water pressure/flow

Just changed the engine on my 8.5 for a new one (heating element had failed), when the shower is set to the colder half of the temperature scale the water flow/pressure out the shower head is good and as it was before the engine change. But now as soon as I turn the dial towards the hotter temperatures the flow drops off quite a lot and seems to have far less pressure/flow than before. What could be causing this?
Asked 4 years ago by Ashley Knowles, London
There shouldn't be anything that is causing this except that the incoming water temperature will now have started to drop.


With a 8.5Kw heater you should expect about 4.5lts per min with a 25 degree temperature rise.

So If the water is coming in to your house at 15 degrees and you are showering at 40 degrees you should expect approximately 4.5lts per min.

Answered 4 years ago by George Thomson

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