Novel speed-controlled exhaust-air to supply-air heat pump combined with a ventilation system

摘要

This paper presents the detailed steady-state measurement results of a novel speed-controlled exhaust-air to supply-air heat pump combined with a ventilation system. Compared with conventional systems, the heating power can be more than doubled to approximately 2.5 kW using recirculation air. Therefore, such cost-effective systems can be utilized not only in high-energy-efficient buildings but also in buildings with higher heating loads, such as in case of renovations. A functional model was developed and tested in the laboratory. The measurement results demonstrated an overall system performance of over 4.5 for minimal heating power at +10 degrees C and 2.5 for maximum heating power at - 7 degrees C. A simplified physical model for refrigerant cycle was presented and validated. It provided results with a measurement accuracy of 8%. The model was used to demonstrate further optimization potential. According to these results, a 5% improved system performance can be achieved by increasing the condenser size.