MULTISTAGE THERMOSTAT USING MULTIRATE INTEGRAL ACTION AND EXPONENTIAL SETPOINT CHANGE

A multistage thermostat means that is adapted for use with equipment such as a heat pump and auxiliary heat and which effects efficient operation upon a temperature setup after a nigh setback function by introducing an exponential change in the apparent control setpoint. The sensitivity of the signal processing channel of the system is altered to maintain stability. The system further contains a power-up reset function that also alters the signal processing channel for rapid reestablishment of normal control.