507428-01
32
Table 2. Alert Codes and Troubleshooting
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.
Alert
Code
Steps to clear
Alert Text
Priority
124
Critical
(Thermostat / Furnace / Air Handler /
Outdoor Unit / Equipment Interface
Module / Damper Control Module))
The thermostat has lost communica
tion with the
(furnace, airhandler or
outdoor unit)
for more than 3 minutes.
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.
131
Critical
(Thermostat / Furnace / Air Handler /
Outdoor Unit / Equipment Interface
Module / Damper Control Module))
The
(Thermostat, furnace, airhandler
or outdoor unit)
control parameters
are corrupted.
Reconfigure the system. Replace the control if heating or cooling is not avail
able.
132
Critical
(Air Handler / Damper Control Mod
ule) The device's control software is
corrupted.
Recycle power. If failure reoccurs, replace the control. System reset is re
quired to recover.
180
Critical
(Furnace / Air Handler / Outdoor Unit/
Equipment Interface Module) The
thermostat has found a problem with
the
(furnace, airhandler or outdoor
unit)
outdoor sensor.
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.
290
Critical
(Furnace) There is a problem with the
furnace ignition circuit.
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.
345
Critical
(Air Handler / Equipment Interface
Module / Heat Pump) The “O” relay on
the airhandler has failed. Either the
pilot relay contacts did not close or
the relay coil did not energize.
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.
