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4–37
T-340
4.11 CONTROLLER ALARM INDICATIONS
Table 4–6 Controller Alarm Indications
Alarm Code
Cause
Components
Troubleshooting
Corrective Actions
AL03
Loss of Super
-
heat Control
Superheat has re
-
mained below 1.66°C
(3°F) degrees for five
minutes continuously
while compressor run
-
ning.
Compressor drawing
more than 2.0 amps,
compressor pressure
ratio is greater than
1.8, and Electronic Ex
-
pansion Valve (EEV) is
at 0% open.
Electronic Expan
-
sion Valve (EEV)
Check the operation of
the EEV using Cd41.
Replace EEV if defec
-
tive.
Evaporator Tem
-
perature Sen
-
sor(s) ETS &
ETS1.
Verify accuracy of tem
-
perature sensors, refer
to Sensor Checkout Pro
-
.
Replace ETS or ETS1 if
defective.
Evaporator Fans Confirm fans operating
properly.
Replace fan(s) if defec
-
tive, refer to EVAPORA
-
TOR FAN MOTOR
ASSEMBLY
AL05
Manual Defrost
Switch Failure
Controller has detected
continuous Manual De
-
frost Switch activity for
five minutes or more.
Keypad
Power cycle the unit.
Resetting the unit may
correct problem, monitor
the unit.
If the alarm reappears
after 5 minutes replace
the keypad.
AL06
Keypad or
Keypad Harness
Fail
Controller has detected
one of the keypad keys
is continuously activity.
Keypad or Har
-
ness
Power cycle the unit.
Resetting the unit may
correct problem, monitor
the unit.
If the alarm reappears
replace the keypad and
harness.
AL07
Fresh Air Vent
Open
The VPS is reading
greater than 0 CMH
while unit is in frozen
mode or XtendFRESH
active.
Vent Position
Sensor (VPS)
Manually reposition vent
and confirm using Cd45.
Refer to VENT POSI
-
TION SENSOR SER
-
.
If unable to obtain zero
reading, replace defec
-
tive VPS.
AL08
High Compres
-
sor Pressure
Ratio
Controller detects dis
-
charge pressure to
suction pressure ratio
is too high.
The controller will at
-
tempt to correct the sit
-
uation by restarting the
compressor.
Discharge Pres
-
sure Transducer
(DPT)
Confirm accurate DPT
pressure readings, refer
to MANIFOLD GAUGE
.
Replace DPT if defec
-
tive.
AL10
CO
2
Sensor
Failure
Alarm 10 is triggered
when the CO
2
sensor
voltage is operating
outside of the 0.9 v to
4.7 v range, or if the
sensor is out of range.
This is a display
alarm and has no
associated failure
action.
Refer to eAutoFresh
manual.
The alarm is triggered off
when voltage is within
operating range.