Trane ACONT900AC43UA Service Manual page 96

Charge Assist™
Does the ambient temperature and the DC voltage or
its resistance in ohms read at the Ambient Tempera-
ture Sensor plug J7 agree with the temperature, resis-
tance and voltage chart? (See Reference Materials)
Yes: Unplug and re-plug the Ambient Temperature
Sensor plug (Figure 38) several times to insure it is
making good contact with the control pins. Turn off
the 24 volts AC to the Charge Assist™ Control and
then re-power the control. If the 5 flash codes con-
tinue to be displayed, replace the Charge Assist™
Control.
No: Unplug and re-plug the Ambient Temperature
Sensor plug J7 (Figure 38) several times to insure
that it is making good contact with the Charge As-
sist™ Control plug, then re-check the DC voltage at
plug J7 or unplug the sensor and read the resis-
tance of the sensor. If the DC voltage or resistance
at plug J7 and the ambient temperature still does
not agree with the temperature, resistance and volt-
age chart, replace the Ambient Temperature Sen-
sor.
Figure 38
Fault LED flash code of 6, Err code 67
Displayed on heat pump Comfort Controls only. This
sensor is used only on heat pump models. The fault
LED (Figure 36) will be flashing in groups of six flashes.
This indicates that the Coil Temperature Sensor is read-
ing out of range. Read the DC voltage at the Charge
Assist™ Control Coil Temperature Sensor plug J6 with
CA - A 16
the sensor plugged in or unplug the sensor and read
the resistance of the sensor (Figure 39).
Figure 39
Does the coil temperature and the DC voltage or its
resistance in ohms read at the Coil Temperature Sen-
sor plug J6 agree with the temperature, resistance and
voltage chart? (See Reference Materials)
Yes: Unplug and re-plug the Coil Temperature Sen-
sor plug J6 (Figure 40) several times to insure it is
making good contact with the control pins. Turn off
the 24 volts AC to the Charge Assist™ Control and
then re-power the control. If the 6 flash codes con-
tinue to be displayed replace the Charge Assist™
Control.
No: Unplug and re-plug the Coil Temperature Sen-
sor plug (Figure 40) several times to insure that it
is making good contact with the Charge Assist™
Control plug J6, then re-check the DC voltage at
plug J6 or unplug the sensor and read the resis-
tance of the sensor. If the DC voltage and tempera-
ture or resistance and temperature does not agree
with the temperature, resistance and voltage chart,
replace the Coil Temperature Sensor.