1 flash
Moderate
Goodman · HVAC Systems (AC, Furnaces & Heat Pumps)
Lockout Retry
Quick Answer
Error code 1 flash on your Goodman HVAC Systems (AC, Furnaces & Heat Pumps) means: Lockout Retry. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Turn off furnace power for 60 seconds to clear the lockout, then restore power
2
After reset, observe the ignition sequence for the specific failure point
3
Check the igniter for cracks or excessive wear and measure resistance (40-200 ohms typical)
4
Clean the flame sensor with emery cloth and verify flame current above 1.5 microamps
5
If lockout recurs after reset, a licensed HVAC technician should perform a full ignition system diagnosis
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Hot surface igniter
Flame sensor
Control board
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