Carrier 42QN8A55140 Main Printed Control Circuit Board

The Carrier 42QN8A55140 Main Printed Control Circuit Board is a single-unit replacement PCB that serves as the primary control module for compatible Carrier and Goodman HVAC equipment. As the main printed circuit board (PCB), it coordinates thermostat inputs, sensor data, and actuator outputs to drive heating, cooling, and fan operations. This part is identified by the number 42QN8A55140 and is sold as a standalone unit. Some listings describe LED indicators on the board to convey status at a glance. When replacing, ensure exact part-number compatibility with your unit and use the appropriate harness connections and mounting pattern specified by Carrier components. This replacement PCB is designed to fit configurations that use Carrier’s standard main-control board layout for appropriate systems; verify your model’s requirements against the 42QN8A55140 specification before purchasing.