Book excerpt: This fully illustrated handbook takes an in-depth look at recent innovations in heat pump technology and applications, providing the reader with the information needed to understand the principles used in all types of air-source and water-source heat pumps, including multi-unit systems. Readily understandable guidelines will assist the engineer, specifier or technician in determining the appropriate system for a specific application, as well as in installing the system properly. System maintenance, troubleshooting and repairing are thoroughly covered. Other topics include fundamentals of refrigeration applicable to heat pumps, and heat pump components and circuitry.