24 June 2014
There are about 277 000 single-family houses in Sweden which are heated by
direct acting electric heaters. In these houses it is very common to install an air-to-air heat pump in order to reduce the electricity use. However, this type of heat pump does not heat
the domestic hot water. This paper presents a newly developed solar air heat pump designed for energy efficient production of domestic hot water. In this heat-pump solution solar heating is integrated into the refrigerant circuit. The way the application is designed will decrease the
need for defrosting of the system which increases its water heating efficiency. The solar air heat pump also allows for different operating modes depending on operating conditions with the intention to utilize renewable energy sources as much as possible.