Intentionally reduce compressor efficiency

[Jaytee]

Hi, I have a thermia air source heat pump with a 5.5kw compressor and rated capacity of 17kw. It has a combined hot and cold heat exchanger and water loops. For the radiator and ground loop. I am using it for central air-conditioning as a water chiller.

I have replumbed it so the hot side is cooled to air and the cold side chills the integral 180 liter water tank which is part of the chilled water loop.

The system cools 5 bedrooms but I find 17kw is too much capacity and the compressor duty cycle is not ideal.

Does anyone have any idea on how to drop the cooling efficiency to around. 10kw? I have Control of the hot side by way of the circulation pump flow and the hot radiator air fan speed.

The evaporation valve has a diaphragm control based on the cold heat exchanger temperature by the looks of it.

An odd question I know but any suggestions are welcome!

[sterl]

Put an inverter on the compressor to run it at a lower speed.