What It Means
- Control Lockout
Lennox Ducted Heating
Lennox Error Code Two Flashes
Ducted Heating:
Causes & actions from Lennox
How it shows
- a3 diagnostic led: Two Flashes
Failed to Sense or Sustain Flame. Check Gas Valve, Burners, Spark Electrode and Wire, Flame Sensor. Replace Control If All OK.
Applicable models & manual sources
- G24M
Control Lockout
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
What should you check next?
Continue in ACLogics with guided diagnosis for your equipment and symptoms.
