A gas heat pump system powered by natural gas, propane or similar gaseous fuel is disclosed. The system uses heat recovery and heat addition to manage efficient heating and cooling cycles. In a cooling cycle excess heat is vented to the atmosphere while in a heating cycle, excess heat is used to heat a subject structure and to prevent frost from forming on outdoor heat exchangers. A control system monitors the system's operation and corrects abnormal operational conditions or shuts down the system until the system can be manually inspected. The costs of system operation are less than electric systems because of the efficiencies and use of natural gas or propane.