Lennox 11U61 Setup And Installation Manual page 32

Table 2. Alert Codes and Troubleshooting
Alert
Priority Alert Text
Code
(Thermostat / Furnace / Air Handler /
Outdoor Unit / Equipment Interface
Module / Damper Control Module))
124 Critical
The thermostat has lost communica­
tion with the (furnace, air­handler or
outdoor unit) for more than 3 minutes.
(Thermostat / Furnace / Air Handler /
Outdoor Unit / Equipment Interface
Module / Damper Control Module))
131 Critical
The (Thermostat, furnace, air­handler
or outdoor unit) control parameters
are corrupted.
(Air Handler / Damper Control Mod­
132 Critical ule) The device's control software is
corrupted.
(Furnace / Air Handler / Outdoor Unit/
Equipment Interface Module) The
thermostat has found a problem with
180 Critical
the (furnace, air­handler or outdoor
unit) outdoor sensor.
(Furnace) There is a problem with the
290 Critical
furnace ignition circuit.
(Air Handler / Equipment Interface
Module / Heat Pump) The "O" relay on
345 Critical the air­handler has failed. Either the
pilot relay contacts did not close or
the relay coil did not energize.
507428-01
Critical alerts are displayed on Home (user) screen, in the Homeowner alert button, and in
the Installer alert button. Minor and Moderate alerts are found only in the Installer alert
button.
Steps to clear
Equipment lost communication with the thermostat. Check the wiring connec­
tions, ohm wires and cycle power. The alarm stops all associated HVAC oper­
ations and waits for a heartbeat message from the unit that's not communicat­
ing. The alarm/fault clears after communication is re­established.
Reconfigure the system. Replace the control if heating or cooling is not avail­
able.
Recycle power. If failure re­occurs, replace the control. System reset is re­
quired to recover.
In normal operation after control recognizes sensors, the alarm will be sent if
valid temperature reading is lost. Compare outdoor sensor resistance to tem­
perature/resistance charts in unit installation instructions. Replace sensor pack
if necessary. At the beginning of (any) configuration, furnace or air­handler
control will detect the presence of the sensor(s). If detected (reading in range),
appropriate feature will be set as 'installed' and shown in the 'About' screen.
The alarm/fault will clear upon configuration, or sensing normal values.
The system will go into Watchguard mode. Measure resistance of hot surface
igniter. Replace the hot surface ignitor it is not within specifications. The alarm/
fault will clear on next successful ignition.
O relay / Stage 1 failed. Pilot relay contacts did not close or the relay coil did
not energize. Replace control. Cleared after the fault recovered following reset.
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