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Goodman Furnace 1 flash: Ignition lockout (no flame)

Updated October 2026 · Sourced from Goodman documentation

🧭 Check a few things first

The control tried three times to light the burners and could not sense flame, so it locked out. The control resets after one hour, or by turning the thermostat off for more than 5 and less than 20 seconds and back on, or by turning off the furnace disconnect for at least 5 seconds.

Is it safe to keep running? Check the steps below first. If the furnace keeps locking out, call a licensed technician. Igniter, flame sensor and gas supply checks are service work.

1 flash at a glance

Code / how it showsMeaningApplies to
1 flash
Diagnostic LED seen through the blower door window
Ignition lockout (no flame)Goodman GMS8 / Amana AMS8 / GDS8 / ADSS8 80% single-stage gas furnaces (older flash-code control)

Check this first

Only steps a homeowner can do safely. Do not open electrical panels or the burner area.

  1. Check the thermostat is set to Heat, set above room temperature, and has fresh batteries if it uses them.
  2. Make sure the manual gas shutoff valve is open, following the lighting instructions on the furnace label.
  3. Turn the thermostat off for more than 5 and less than 20 seconds, then back on (the manual's reset), or turn the furnace power off for at least 5 seconds.
  4. Look outside at the furnace vent and intake pipe ends. Make sure snow, leaves or a nest are not blocking them. Look only, do not touch the pipes.

🛑 Stop and call a licensed pro if

  • If the furnace keeps locking out, call a licensed technician. Igniter, flame sensor and gas supply checks are service work.
  • You smell gas. Leave the house, do not touch switches, and call your gas utility from outside.
  • Flame rollout, limit or pressure switch codes that come back after one reset.
  • Anything involving the control board, gas valve, flame sensor, igniter or venting.
  • A carbon monoxide alarm sounds. Get everyone outside and call 911 or the fire department.

Safe first steps for any Goodman code

  1. Count the LED flashes through the blower door window before you switch anything off. Cutting power can clear the code.
  2. Replace or clean the furnace air filter.
  3. Check the thermostat: correct mode, set above room temperature, and fresh batteries.
  4. Make sure the furnace power switch and breaker are on. If the furnace has locked out, turning the power off and back on once restarts it.
  5. Make sure the gas valve is in the ON position, following the lighting instructions on the furnace label only.
  6. On high-efficiency furnaces, look at the outside vent and intake pipes for snow, ice, leaves or nests (look only, do not take pipes apart).

Source: Goodman GMS8/AMS8/GDS8/ADSS8 80% Single Stage Service Instructions RS6612006 (July 2013), pp.37-39. Codes are series-specific, so your unit's own manual is the final word. Reviewed October 2026.

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Related Goodman codes

2 flashes : Pressure switch stuck closed3 flashes : Pressure switch stuck open4 flashes : Open primary or auxiliary limit5 flashes : Flame sensed with no call for heat6 flashes : Open rollout limit7 flashes : Low flame sense signal8 flashes : Igniter circuit fault or poor groundContinuous flash : Reversed polarity or poor ground (continuous or rapid flash)E0 : Lockout after three failed ignition attemptsE1 : Low-stage pressure switch closed at start of heatingE2 : Low-stage pressure switch circuit openE3 : Primary limit circuit open (furnace overheating)

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