Q.1.61 January 2023
Page 15
KE2 Evap
OEM
Alarm Troubleshooting Guide
© Copyright 2023 KE2 Therm Solutions, Inc., Washington, Missouri 63090
21214V3.0
Troubleshooting Tables
Alarm & Alarm Name
Description
Variables & Setpoints Corrective Action
Basic
Display
Combo
Display
Web-
pages
Hd2
Hd2
HIGH
MONITOR
TEMP2
High
Mon2
Temp
Alarm
Yellow LED is illumi-
nated. Controller will
attempt to continue
to operate system
while this alarm is
present.
Combo aux monitor
temp reading above
MON TMP HI ALRM or
below MON TMP LO
ALRM for longer than
MON TMP AL DLY.
Variables
DISP AUX2 STATUS
DISP AUX3 STATUS
Setpoints
MON TMP2 HI ALRM
MON TMP2 LO ALRM
MON TMP2 AL DLY
MON TMP3 HI ALRM
MON TMP3 LO ALRM
MON TMP3 AL DLY
• See if the refrigeration system is running, or in the case of a low alarm, whether the
refrigeration system is over-cooling due to a stuck thermostat, solenoid, EEV etc.
• Infiltration from an adjoining freezer or outdoor wall may cause a low alarm. Ad-
dress the infiltration and/or move the sensor to a more appropriate location.
• Ensure that the relevant Monitor Temp Alarm setpoint is high enough, and the
delay is long enough, so that the alarm does not trigger during normal loading or
defrost.
Ld2
Ld2
LOW
MONITOR
TEMP2
Low
Mon2
Temp
Alarm
Hd3
Hd3
HIGH
MONITOR
TEMP3
High
Monitor
Temp3
Alarm
Ld3
Ld3
LOW
MONITOR
TEMP3
Low
Monitor
Temp3
Alarm
EA1
EA1
DISPLAY
EXTERNAL
ALARM 1
Disp Ex1
Alarm
Yellow LED is illumi-
nated. Controller will
attempt to continue
to operate system
while this alarm is
present.
Combo External
Alarm input is active.
Variables
DISP AUX1 STATUS
DISP AUX2 STATUS
DISP AUX3 STATUS
Setpoints
AUX1 FUNCTION
AUX1 SWITCH STATE
AUX2 FUNCTION
AUX2 SWITCH STATE
AUX3 FUNCTION
AUX3 SWITCH STATE
• Troubleshoot the device connected to the Combo Display auxiliary input to dis-
cover why it is in alarm condition and resolve the issue.
• If the device is not in alarm, check to make sure the device is connected to the ap-
propriate position on the Combo Display board (TEMP1, TEMP2 or TEMP3).
• Review the Combo Display settings to make sure they match the type of device
connected to the controller. AUX1, AUX2, or AUX3 FUNCTION should be set to
EXTERNAL ALARM as appropriate to set the aux input to function as an external
alarm input.
• Verify the aux input state (AUX1, AUX2, or AUX3 SWITCH STATE) is appropriately set
to OPEN or CLOSED to match the input’s functionality. If the controller is alarming
when the external device is not active, changing the state will reverse the logic.
EA2
EA2
DISPLAY
EXTERNAL
ALARM 2
Disp Ext2
Alarm
EA3
EA3
DISPLAY
EXTERNAL
ALARM 3
Disp Ext3
Alarm
Pbt
Pbt
HELP
Panic
Button
Alarm
Red LED is illumi-
nated on KE2 Basic
Display. All LEDs
are blinking on KE2
Combo Display and
buzzer beeping.
Refrigeration will
stop while this alarm
is present.
• Check walk-in immediately for any trapped personnel.
• Press and hold Panic Button for 3 seconds to clear.
LPCO (Low Pressure Cut-Out control) Only
Pdt
Pdt
PUMP-
DOWN
TIMEOUT
Pump
Down
Timeout
Low Pressure Cut-Out
Time exceeded be-
fore suction pressure
reached Low Pressure
Cut-out.
Variables
PrS – Suction Pressure
Setpoints
LPC – Low Pressure
Cut-out
LPt – Max Time for LPCO
• Check LPt to see if the Low Pressure Cut-out Time is too short.
• Check LPC to see if the Low Pressure Cut-out is set too low. LPC should be set to
refrigeration unit manufacturer’s recommendation.
• Confirm EEV is operating properly. See High/Low Superheat corrective actions for
troubleshooting the EEV.
• Follow compressor manufacturer’s troubleshooting guide to ensure compressor is
operating properly.
• If controller is operating a liquid line solenoid instead of compressor contactor, LPCO
control should not be enabled. Set LPt to 0 to disable LPCO control.
SCC
SCC
SHORT
COMP
CYCLE
Short
Com-
pressor
Cycle
Compressor started
excessive number of
times due to suction
pressure in off mode,
or compressor cut-
out excessive number
of times due to suc-
tion pressure while in
refrigeration mode.
Variables
PrS – Suction Pressure
Setpoints
LPC – Low Pressure
Cut-out
LPd – Pressure Differen-
tial for LPCO
• Check LPC to see if the Low Pressure Cut-out is set too low. LPC should be set to
refrigeration unit manufacturer’s recommendation.
• Check LPd to see if the Pressure Differential for LPCO is too small. LPd should be set
to refrigeration unit manufacturer’s recommendation.
• Confirm EEV is operating properly. See High/Low Superheat corrective actions for
troubleshooting the EEV.
• High superheat conditions can cause short cycling of the compressor while calling
for refrigeration. Troubleshoot the refrigeration system for common causes of high
superheat (restriction in the liquid line, flash gas, insufficient subcooling, dirty con-
denser etc.).
• Confirm suction temperature is reading correctly. Follow Suction Temp Alarm cor-
rective actions.
• Confirm pressure transducer is reading correctly. Follow Pressure Sensor Alarm cor-
rective actions.
– KE2 Combo Display Only