Alarm Codes And Descriptions - Lennox icomfort Setup Manual

Alarm ID Message Name
10 Unknown Device Detected − DEVICE2
11 Missing DEVICE2
12 Incomplete System
14 Too Many Devices of the Same Type
18 Low Ambient HP Heat Lockout
19 High Ambient Auxiliary Heat Lockout
29 Over Temperature Protection
30 Low Temperature Protection
31 Lost Communication with DEVICE2
32 Asynchronous Reset DEVICE2
34 Must Program Unit Capacity for DEVICE2
35 Incorrect Operation of DEVICE2
105 Communication Problem
110 Low AC Line Voltage
113 High AC Line Voltage
114 AC Line Frequency/Distortion Problem
115 Low Secondary (24VAC) Voltage
116 High Secondary (24VAC) Voltage
120 Unresponsive DEVICE2
124 Active Subnet Controller Missing
Alarm Codes and Troubleshooting
Action required to Clear/Recover
Reconfigure the system. Press and hold Lennox Logo, press setup tab, press start, and press confirm. If still
persists, then check all DEVICE connections to make sure they are icomfort compatible.
Check all connections and cycle system power. If problem persists, then reconfigure the system (procedure
mentioned above).
Thermostat did not find an Indoor Unit. Check connections and cycle power. Replace board if no response.
Thermostat found more than one outdoor unit, or more than 1 indoor unit, or more than 1 thermostat connected
to the system. Check wiring and remove duplicate equipment.
Notification only − Outdoor Temp is below the Low Balance Point. HP will not be used to service a Heating Call.
Notification only − Outdoor Temp is above the High Balance Point. Indoor Unit (Furnace or Electric Heat) will not
be used to service a Heating Call.
Indoor Temp went above 99ºF during a heating or cooling call. Heating is not allowed. Check that Thermostat
Sensor is accurate. Check that Heating Equipment is not stuck ON (reversing value, etc.). Select system mode
to cooling to try and cool the indoor space.
Indoor Temp went below 40ºF. Cooling is not allowed. Check that cooling equipment is not stuck ON. Check
accuracy of the thermostat temperature. Try to heat the space to above 40ºF.
DEVICE2 is not communicating to the thermostat for more than 3 minutes. Check connections if fault persists,
then cycle power.
DEVICE2 is resetting by itself. Check power connections, and check 24VAC voltage at DEVICE. The alarm is
only cleared by pressing the clear button on the Installer Alerts Tab. If fault persists after checking connections,
replace board.
DEVICE2 is missing the programmed unit capacity. Go to DEVICE2 and program unit capacity manually. See
unit IOM for instructions.
DEVICE2 did not follow the command of the thermostat. Check connections and cycle power.
Equipment is unable to communicate. Check for miswired and/or loose connections and check for a high volt-
age source of noise close to the system (welder etc.).
Line Voltage Low (Voltage lower than nameplate rating). Check voltage.
Line Voltage High (Voltage higher than nameplate rating). Check voltage.
No 60 Hertz Power (Check voltage and frequency).
24 Voltage Low (Range is 18 and 30 volts ). Check voltage.
24 Voltage High (Range is 18 and 30 volts ). Check voltage.
Usually caused by delay in outdoor unit responding to indoor unit poling recycle power, check wiring.
Equipment lost communication with the thermostat. Check connections and cycle power on the thermostat.
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icomfortt Touch Screen 7−Day Programmable Thermostat