Microcomputer instrumentation to reduce residential energy use

A microcomputer-based instrument controls residential space and water heating to provide a reduction in the consumption of energy. Using an RCA 1802 microprocessor and CMOS logic devices, the controller monitors ambient and water temperatures with thermistors, and operates the furnace and water-heating processes through solid-state relays. Programmable over a one-week cycle with up to eight set points each day, the instrument conserves energy and saves money by cutting back the temperature in parallel with a family's living profile. At an example utility rate of $0.06/kW h, a typical family will reduce space heating use by 9 percent and water heating by 7 percent for an overall savings of 6 percent or 145.00 dollars in their total yearly energy bill.