DUAL TEMPERATURE CONTROL CIRCUIT

摘要

DUAL TEMPERATURE CONTROL SYSTEM A temperature control system for providing an automatic reduction in the temperature of a room or a house during the nighttime hours which requires only the conventional two conductor wiring between the furnace and the thermostat thereby avoiding the necessity of adding to or replacing the existing wiring between the furnace and the thermostat. A first embodiment of the system includes a temperature responsive element, a heater near the temperature responsive element for providing supplemental heating of the element, a conventional furnace control, a clockoperated current control for the heater, and a diode steering circuit for directing one portion of an alternating current waveform through the heater current control and the heater, and another portion of the alternating current waveform through the temperature responsive element and the furnace control for providing independent control of the heater and the furnace control. The heater provides supplementary heating of the temperature responsive element during the nighttime hours to establish an apparent room temperature which is higher than the actual room temperature so that the thermostat element will lower the room temperature during the nighttime hours. A second embodiment of the system includes two temperature responsive elements, one for setting the low temperature and the other for setting the high temperature, a conventional furnace control, a clock-operated switch for activating either the high or low temperature responsive element, and a diode steering circuit for directing one portion of an alternating current waveform through the low temperature responsive element and the furnace control, and another portion of the alternating current waveform through the high temperature responsive element and the furnace control for providing independent control of the furnace by the low temperature element and the high temperature element in accordance with the timer switch. Accordingly, the low temperature responsive element may be set at the desired nighttime temperature and the high temperature responsive element can be set at the desired daytime temperature with each being activated for the appropriate time period by the timer switch.