There is a big variation in efficiency claims. Who do I believe?
A. There are a great variety of heat pump applications and uses, resulting in a wide range of efficiencies. Just be mindful that there is sometimes a tendency to quote best-case figures. The average annual efficiency could be significantly less than first expected due to many reasons. The IMPORTANT chart above demonstrates how dramatically the efficiency varies with heated water temperature. Attention to design details is the key to achieving high energy efficiency.
