Thermostat shows heat or cool call active but Goodman equipment does not start

Safety first: Turn off power to the furnace/air handler and outdoor unit at the breakers before inspecting wiring.

Steps to restore control signal:

• 1. Verify call at thermostat: Confirm the thermostat indicates a call for heat or cool (icon or status).
• 2. Check voltage at furnace board: With power on and call active, measure 24VAC between the relevant call terminal (W or Y) and C at the Goodman control board. If no voltage, the issue is between thermostat and board.
• 3. Inspect wiring: Tighten all low-voltage terminals at the control board and thermostat. Repair any damaged cable.
• 4. Check safety switches: Inspect condensate float switches or other external safeties wired in series with Y or W. If a switch is open due to a fault (e.g., full drain pan), correct the underlying issue and reset the switch.
• 5. Replace thermostat or board: If wiring and safeties are intact but the signal never appears at the board, suspect a failed thermostat or, less commonly, a failed control board input.