Developement of energy efficient indirect heat pump

Research and measurements at SP show that heat exchangers with other geometries than finned round tube setting gives indirect heat pump systems a promising energy and noise performance. This could compensate the disadvantages that come with an extra heat exchange stage. When indirect heat pumps have similar energy performance as the best direct expansion heat pumps the indirect technology can compete fully on the market. This will result in heat pumps which are easier to install, that provide more reliable operation and that will cause much less noise related disturbance.

The aim of the project is to develop and examine a heat exchanger design that enables an energy efficient and quiet heat pump that the heat pump manufacturers can continue to develop for both the Swedish and the European heat pump market. Therefore, we will examine different heat exchangers with a model based on empirical correlations and heat exchanger theory and build and perform measurements on heat pump prototypes.


Swedish Energy Agency through Effsys Expand
Airec AB
Danfoss värmepumpar AB

Time schedule

May 2015 – June 2017

Project partners
Airec AB
Danfoss värmepumpar AB


Related Information

Contact Persons

Ola Gustafsson

Phone: +46 10 516 51 20

RISE Research Institutes of Sweden, Phone 010-516 50 00, E-mail

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