What It Means
- STRIKE 3 EVAPORATOR FROZEN COMPRESSOR 1
Lennox Unit controller
Lennox Error Code 33
Unit controller
Causes & actions from Lennox
How it shows
- M4 alarm code: 33
• Compressor is locked out. Check SST sensor, air flow, charge, coil, air filter and outside air temperature. • Number of occurrences is set using Parameter 81 (max freeze stat occ). Default is 3 occurrences.
Applicable models & manual sources
- MODEL L - M4 UNIT CONTROLLER
STRIKE 3 EVAPORATOR FROZEN COMPRESSOR 1
MODEL L - M4 UNIT CONTROLLER, M4 Unit Controller
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.
