RV Appliance Code Atlas

Suburban/Atwood lock out fault code — Furnace

Applies to: Suburban gas furnace

What lock out means

The Suburban furnace guide describes lockout after the furnace fails to ignite after multiple attempts.

Owner-safe checks

  • Turn the thermostat off.
  • Check that intake and exhaust vents are not covered.
  • Do not continue cycling the furnace after repeated no-ignition attempts.

Service-only work

  • Ignition, combustion, flame-sense, gas, and board troubleshooting is qualified service.

Safety boundary

Stop after repeated ignition failure. Shut off LP if there is gas odor, soot, or abnormal flame/exhaust evidence.

Official sources

Related symptom guides

All Suburban/Atwood codes and guides