New efficient design for air-air heat pumps

Abstract

In this work a new design for reversible air-air heat pumps is proposed. This design is based on the inversion of the air flow on the ducts, instead of the refrigerant changeover, as is proposed by ASHRAE. Thanks to this modification it is possible to use any conventional air-air refrigeration machine for air conditioning as a reversible heat pump. The new design is more efficient, especially when a great air quality it is required in the building and therefore a larger amount of outdoor air it is used. Compared with traditional designs it also increases the efficiency as the outdoor temperatures become more extreme. This improvement will make it possible to use heat pumps, with acceptable performances, in more rigorous climates than those in which they are used today.