What It Means
- Active communicating thermostat signal missing for more than 3 minutes.
Lennox Ducted Heating
Lennox Ducted Heating Error Code E124
Ducted Heating:
Causes & actions from Lennox
How it shows
- Integrated control 7-segment display: E124
Equipment lost communication with the thermostat. Check four wiring connections, ohm wires and cycle power at the thermostat. Alert stops all services and waits for heartbeat message from thermostat (subnet controller). Cleared after valid thermostat (subnet controller) message is received.
Other manual wording
SLP98UHV, SLP99UHV
Equipment lost communication with the thermostat. Check connections and cycle power on the thermostat.
Applicable models & manual sources
- SL280DFNV
Active communicating thermostat signal missing for more than 3 minutes.
- SL280UHV
Active communicating thermostat signal missing for more than 3 minutes.
- SL297UHNV
Active communicating thermostat signal missing for more than 3 minutes.
- SLP98UHV
Active communicating thermostat signal missing for more than 3 minutes.
- SLP99UHV
Active communicating thermostat signal missing for more than 3 minutes.
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.
