Suburban furnace blows cold air, locks out, or hits limit

Use this when a Suburban gas furnace fan runs but heat does not start, the furnace enters lockout, or the FAQ points to a limit-switch condition.

Owner-safe checklist

• Turn the thermostat off and let the furnace complete its blower cooldown.
• Do not keep cycling the thermostat after repeated no-heat or no-ignition attempts.
• Check only visible exterior intake and exhaust openings for blockage before one normal restart.
• Record the thermostat setting, number of start attempts, blower run time, and whether heat ever reached the vents for a dealer or Suburban service center.

Official sources

• Suburban Gas Furnace Operation Guide
• Frequently Asked Questions about Suburban RV Products

Related fault codes

• Suburban/Atwood lock out — Furnace