Energy savings through thermostat setback

A hybrid computer model of a gas-fired forced air furnace with a standing pilot light was used to determine the energy savings effects of day, night, and day-and-night thermostat setback. The major results were: night setback with gas-fired, forced air heating systems will always result in energy savings; setting the thermostat down only during the day saves energy, but at a lower percentage than with night setback; setting the thermostat down at night and also down during the day (dual setback) can save an appreciable amount of energy, i.e., approximately twice the savings as for night setback alone; the greater the duration of thermostat setback and the greater the amount of thermostat setback, the greater the energy savings; and the capacity of the gas-fired, forced air heating system must be properly sized to achieve space temperature pickup in a reasonable amount of time. Comparable energy savings for oil-fired and electrically heated hot air systems and for hot water heating systems are predicted. (LCL)