More and more heat pumps are being fitted with efficient parts such as a DC compressor, an electronic expansion valve and/or an EC fan. the aim is to improve efficiency. However, the use of efficient components alone is not enough because intelligent control is also required to really make a difference.
The compressor in a heat pump system is the primary consumer of energy. A logical choice is therefore to use an energy-efficient DC compressor. The higher output of these DC motors immediately creates a major energy saving. The drive for the DC compressor does require what is called an inverter. A heat pump control with advanced inverter control ensures that the compressor is actually able to be efficient with the required energy and that the power of the heat pump can be controlled on the basis of the heat demand.With an electronic expansion valve the size of the aperture is controlled by a stepper motor. On the basis of a number of temperature measurements the heat pump control calculates the optimum position for the electronic expansion valve. Proper control of the electronic expansion valve ensures that the heat pump is always able to find an optimum working point. As a result of this the efficiency of the heat pump is increased. An EC fan or EC pump in use generates an energy saving of no less than 60 percent compared to the commonly used AC motors. Via the heat pump control the speed of these types of fans and pumps can also be easily adjusted and, as a result, optimised.
An integrated weather-dependent control with room temperature compensation harmonizes the heat that the heat pump has to deliver to the actual internal and external temperatures. As a result of this the heat pump control is able to respond immediately to external temperature changes and adjust the capacity if required. This control contributes to the further efficiency optimisation.
For serviceability a good user-interface has become essential, especially with advanced heat pump systems. To start with, the user wants clear status information. Settings and historical data with regard to the appliance components — that are already controlled intelligently by the heat pump control — can now be easily displayed via the user interface. This offers the possibility of generating more specific fault codes.
For air/water heat pumps there are now many component options that can further reduce the energy consumption. To achieve optimum control of these advanced components the role of the heat pump control has become essential. Appliance expertise and integration of control functions have been the decisive factors in achieving a successful end product.