Goodman GMEC960803BN Error Code Red 3 Flashes: 1st-Stage Pressure Switch Stuck Open / Inducer Error
What Does Code Red 3 Flashes Mean?
Three red flashes on the Goodman GMEC960803BN control board indicate that the first-stage (low-fire) pressure switch is stuck open. The pressure switch is a safety device that verifies the inducer motor is creating enough draft to safely vent combustion gases before the burners are allowed to ignite.
When the inducer motor starts, it creates a vacuum that pulls the pressure switch closed. If the switch does not close, the control board blocks ignition and displays this fault code. The inducer motor will continue running, but the furnace will not proceed to the ignition stage.
The most common cause is a blocked or restricted exhaust vent pipe — ice buildup in winter, bird or insect nests, leaves, or other debris at the vent termination. Other causes include a kinked or disconnected pressure switch hose, a faulty pressure switch, or a failing inducer motor that cannot generate sufficient vacuum. In rare cases, the control board's inducer relay may have failed.
Common Causes
When to Call a Professional
Contact a licensed HVAC technician if:
- The vents appear clear but the code persists
- The inducer motor sounds weak, rattles, or does not spin at all
- The pressure switch hose is intact and connected but the switch will not close
- You hear the inducer running but see no evidence of airflow at the vent termination
- The vent run has excessive length or many elbows
✓ Verified against manufacturer service manual — March 2026