Goodman GMVC80 three flashes: pressure switch open after the inducer starts

What Does Error 3 flashes Mean?

On the documented Goodman GMVC80 board, three flashes means the pressure-switch circuit is open when the control expects it closed. It does not prove the pressure switch is defective. The inducer, venting, condensate path, hose, wiring, and available draft all remain part of the diagnosis. Applies to: Goodman GMVC80 condensing gas furnaces This three-flash definition belongs to the GMVC80 instructions cited here. Newer Goodman furnaces can use alphanumeric seven-segment codes instead of this LED pattern, so match the model and the legend on its door before applying the meaning. Owner-safe checks: Listen to one complete heat-call sequence with every furnace panel installed and record whether the inducer starts before the code. | Look at accessible outdoor intake and exhaust openings for visible snow, leaves, nests, or damage without inserting anything. | Photograph the flash pattern twice and capture the model number and door-chart wording before power is changed. Qualified technician: Pressure measurement, hose and condensate inspection, switch testing, vent assessment, and live electrical diagnosis require qualified gas-furnace service. | Never bypass a pressure switch or hold a panel interlock to force an ignition attempt.