Patent ID: 9410713
Filing Date: 2016-08-09
CPC Classification: F24F,H02P,Y02B

Claim Text:
1. An integrated efficient fan controller (EFC) circuit device for controlling a fan of a heating, ventilating and air conditioning (HVAC) system, comprising: an input-output port having a plurality of input terminals and an output terminal for connecting the integrated circuit device with a thermostat and an HVAC system; a triac connected to the output terminal of the integrated circuit for controlling the fan function of the HVAC system; a microprocessor having a plurality of terminals for providing a triggering signal to the gate of the triac; a transistor that acts as a switching element and connects to the microprocessor to turn on/off the microprocessor; and a voltage regulator that acts as a constant voltage source to provide a constant voltage to the microprocessor and the transistor; whereby at least one of the plurality of input terminals switches the transistor to a conducting state that turns on the microprocessor which creates a trigger signal to turn on the triac, the triac providing an output to the circuit device that enables switching OFF the HVAC fan operation when the thermostat is switched OFF, and wherein the circuit device processes a floating state of a thermostat fan output as it enters the input terminals by outputting an OFF state signal in the output terminal to avoid the floating state of the thermostat fan output to falsely trigger the HVAC fan to turn ON.