5
TROUBLESHOOTING
There are system error messages that may appear on the
thermostat screen. See text below for possible system error
messages and their meaning.
Space Temperature Sensor Failure —
If the
space sensor reads less than –50 F or greater than 150 F for 60
consecutive seconds, the sensor is considered failed.
If the space temperature sensor fails, Y1 for all fan coil units
and W for fan coil units with Emergency Heat mode set to On
will turn off. The space temperature display shows "- -". The
fan will continue to run.
If the space temperature is the average of both the local and
remote sensors and one of the sensors fails, the thermostat con-
trols the valid sensor only. The display alternates every 10 sec-
onds between "- -" for the invalid sensor and the reading from
the valid sensor.
Fan Error —
If the thermostat is in the unoccupied mode,
fan auto cannot be changed to continuous fan mode (or F1, F2,
F3). An E7 error message will be displayed in the space tem-
perature digits for three seconds, but the fan selection will not
be changed.
E7 Error —
If the thermostat is configured for continuous
fan and the
fan
button is pressed, an E7 error code will be dis-
played indicating that the fan speed can not be adjusted.
Five-Minute Compressor Timeguard —
This
timer prevents the compressor from starting unless it has been
off for 5 minutes. It can be defeated for one cycle by simultane-
ously pressing the
fan
and
up
keys. The indication of a flash-
ing heat or cool icon means that there is a demand in the space
but the equipment is being held off due to the timeguard timer.
Changing Batteries —
The thermostat can be powered
by the HVAC equipment or by battery power. If there is no
lighting until the user touches a button, it is battery powered.
When the thermostat uses electricity, the batteries (if installed)
take over if the electricity goes out.
When powered by batteries, the thermostat's two AA batter-
ies should last about one year. When the batteries have lost
about one-third of their power, a
battery
icon shows up on the
display in the upper right corner with two black bars. If two-
thirds of battery power is lost, the battery icon will display one
black bar. As the batteries get weaker, the icon goes down to
one bar and then none. When the battery icon is less than full,
backlight function will be lost. When the batteries are com-
pletely dead, the thermostat will be unusable.
It is recommended that the batteries be replaced at the one
bar level with two AA alkaline batteries. Batteries are located
in the back of the thermostat, so the thermostat will have to be
removed from the wall. To replace the batteries, perform the
following procedure:
1. Locate the latch at the top of the thermostat. The latch is
located at the center of the top rim.
2. Press the latch down. This will disconnect the thermostat
from the top of the wall plate.
NOTE: The HVAC equipment will shut down.
3. Remove the thermostat from the wall bracket completely
by moving it slightly toward you and lifting it up and off
the lip on the lower edge of the wall bracket.
4. Set the thermostat face down on a flat surface. The batter-
ies are located in the lower right corner.
5. Remove and recycle the old batteries.
6. Install new batteries.
7. Replace the thermostat on the wall bracket by lining up
the two slots on the bottom edge of the back of the ther-
mostat with the two lips on the wall bracket.
8. The HVAC equipment will start back up based on the
previous configuration settings.
