Integrated furnace control

The development of an intelligent control philosophy for hot forced air, residential gas furnaces is addressed. The purpose of the program was to explore the use of electronics in controls for heating appliances. The integrated control is represented as a system consisting of five functional sections: (1) central logic board; (2) complement of sensors; (3) information display; (4) actuated output; and (5) monitoring input. To avoid electrical interference and to improve system cost, it was decided to partition the integrated control into two modules. One module would serve as the user interface device and would be located in the living space. The second module would be the main control module; its location was in the appliance itself. A functional description of the system is given, and the diagnostics and setback/setup are also discussed. Although this integrated furnace control was not intended to become a production item, it served as a vehicle for testing a variety of control concepts