Lennox Select Equipment
Lennox Error Code 4
4 means different things on different Lennox equipment. Choose the equipment you are working on.
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always refer to your unit's service manual.
What does it mean? Select your equipment
- Split & Multi-Split Air handler (indoor), Heat pump (outdoor) Sensor communications issueLocked RotorCommunication abnormal with compressor drive module->
- Ducted Heating Oil furnace (indoor) Low Flame Signal - check flame sensorCad cell resistance >1600 Ohms->
- Packaged Unit Packaged HVAC (outdoor) Limit switch is open and/or high limit has opened three times.Sensor communication issue->
- Equipment not specified high temperature protection: High temperature protection when outdoor ambient temperature exceeds 96°F (35.6°C)->
- Unit controller Unit controller SMOKE DETECTED->
What should you check next?
Continue in ACLogics with guided diagnosis for your equipment and symptoms.
