HVAC Code Lookup

Payne Furnace Code 34.3

Safety faultShown as: Major code 34 on the LED (3 short, 4 long); 34.3 on the display

Flame lost - after successful ignition (flame proven), flame was lost after the heating blower on-delay.

Manual wording: “34.3 FLAME LOST - After successful ignition (flame proven) flame lost after heating blower on delay.”

Documented for: PG80MSU

Likely causes, most common first

  1. Oxide buildup on the flame sensor
  2. Low inlet gas pressure
  3. Poor control ground continuity
  4. Airflow disturbing the flame

What you can safely check yourself

  • Check that the air filter is clean and supply and return vents are open

When to call a technician

Losing flame once the blower starts usually points at gas pressure or flame sensing - have a technician measure flame current and manifold pressure.

A Payne furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.

Source

Other Payne codes