Make sure the main power switch to the Goodman furnace is “On” if the motor won’t start and the door switch is closed. Replace or reset the circuit breaker or fuse.
Remove the filter and clean with a vacuum cleaner or warm, soapy water and let dry, if the motor runs erratically or the blower flame is yellow and uneven. Disconnect the power to the furnace before performing maintenance.
Check the gas supply valve if the error light blinks once, which means ignition failure. Turn the gas supply valve to wide open.
Disconnect power and wait 30 seconds, then restore power if there are two error blinks, which mean the pressure switch has closed. Contact Goodman if the error light returns when the power is restored.
Turn down the thermostat and disconnect power if there are four blinks. Wait 30 minutes to restore power, as the open limit switch has tripped. Contact Goodman if the light continues to blink when the power is restored.