49-5000400 Rev. 5
11
On Board Diagnostics (RARWT_ _)
Low Voltage Detection:
If the 12VDC drops below 10.5V, the
thermostat will switch to “OFF” mode
and flash “Lo”.
When voltage exceeds 10.5V, the display will show a
constant “Lo” and remain in “OFF” mode until a different
mode is reselected by the user.
A/C Freeze-Up Prevention:
In COOL mode, a flashing snowflake icon
indicates that the indoor coil is near freezing, and
that the compressor was turned off.
Recommend increasing airflow by cleaning the filter and
opening vents.
Heat-Pump Auto-Defrost:
In HEAT-PUMP modes, a flashing HEAT-PUMP
icon indicates that the unit is performing an auto-
defrost.
In HEAT-PUMP+FURNACE mode, while auto-defrosting,
the unit will use the furnace.
Heat-Pump Lockout:
In HEAT-PUMP ONLY mode, a
flashing HEAT-PUMP icon AND 25
°
F
(-4
°
C) indicates that the outdoor
temperature dropped below 25
°
F (-4
°
C) and the Heat-
Pump is locked out.
Recommended when expecting temperatures below
25
°
F (-4
°
C) to use HEAT-PUMP+FURNACE or
FURANCE ONLY mode.
