What It Means
- Protocol Upgrade Required
Lennox Equipment not specified
Lennox Equipment not specified Error Code 20
Equipment not specified:
Causes & actions from Lennox
How it shows
- iComfort S30 alert: 20
Priority condition: Service Urgent The thermostat cannot work with one of the system devices because the thermostat firmware needs to be updated first
Applicable models & manual sources
- iComfort S30
Protocol Upgrade Required
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.
