What It Means
- Unsteady thermostat input
Lennox Zone controller
Lennox Error Code 1100
Zone controller
Causes & actions from Lennox
How it shows
- harmony diagnostic led1234: 1100 (led1: on, led2: on, led3: off, led4: off)
This error occurs when a thermostat changes state repeatedly and rapidly, indicating that the thermostat is making intermittent contact and needs attention. The offending thermostat will be ignored for four minutes after the zone control system detects the problem. After four minutes if the signal from the thermostat is steady again, it will be recognized by the zone control system. Disconnect thermostats until error goes away. This will identify the source of bad input. If error remains after all inputs have been disconnected, replace zone control panel.
Applicable models & manual sources
- HARMONY III
Unsteady thermostat input
HARMONY III, X9953
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
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