KE2 Evap
OEM
Alarm Troubleshooting Guide
Q.1.61 January 2023
Page 6
© 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
SSA
SSA
SUCTION
TEMP
SENSOR
T1 Suct
Sensor
Alarm
ONLY ACTIVE WHEN
AN ELECTRONIC
EXPANSION VALVE IS
SELECTED.
Red LED is illumi-
nated. System cannot
operate while this
alarm is present.
Temperature sensor is
shorted or open (not
connected).
Variables
SUt - T1 Suction Temp
rtP - Room (Air) Temp
CLt - Coil Temp
AU1 - Aux Temp 1
AU2 - Aux Temp 2
AU3 - Aux Temp 3
• If temp sensor reads
-88 the cable or sensor
is open, or not con-
nected.
• If temp sensor reads
180+ the input, cable,
or sensor is shorted.
• The majority of sensor alarms and inaccurate readings are caused by cut, burned,
chaffed or otherwise damaged sensor cable. Inspect the length of the cable for any
cut, burned, chaffed or otherwise damaged sections. Repair any damaged sections
• Check that the sensor is inserted into the proper position on the board. The sensor
is not polarized; black and white wires can be inserted in either position on the
connector:
Suction Temp: black connector labeled TSUC.
Air Temp: blue connector labeled TAIR.
Coil Temp: yellow connector labeled TCOIL.
2nd Coil Temp/Aux 1 Temp: green connector labeled AUX1.
Aux 2 Temp: black connector labeled AUX2.
Aux 3 Temp: black connector labeled AUX3.
• The bare stranded wire of the temperature sensor should be inserted so that the wire
is directly touching the gate of the connector. If the gate is contacting the insulation
of the wire, it will not allow the controller to read the sensor.
• If wires have been extended, check for any bad splices, crimps or solder joints where
extended.
• Check the sensor probe. If the sensor cable has been pulled, the sensor probe may
have been damaged, and needs to be replaced.
• To verify accuracy of the sensor, the preferred method is to place the sensor in a
proper ice bath while connected to the controller. View the relevant sensor in the
variables menu, temperature should read around 32.0°F. If adjustment is necessary,
an offset can be applied via the browser interface.
• Sensor accuracy can also be verified using a third party thermometer, however, it
must be calibrated and rated to measure low temperatures.
• Unplug the connector and check that the resistance reading of the sensor matches
the temperature vs. resistance table.
Temperature
°
F
Ohms
-22
19480
-4
12110
14
7763
32
5114
50
3454
68
2387
77
2000
86
1684
104
1231
122
885
• If temperature appears to be within the proper operating range, swap a non-alarming
sensor with the sensor being diagnosed.
• If the new sensor is read properly by the controller, the sensor being diagnosed will
need to be replaced.
• If the sensor was disconnected for diagnostic purposes, return the sensor to the
appropriate location on the controller once diagnostics are complete.
ASA
ASA
AIR TEMP
SENSOR
Air
Sensor
Alarm
Yellow LED is illumi-
nated. Controller will
attempt to continue
to operate system
while this alarm is
present.
Temperature sensor is
shorted or open (not
connected).
CSA
CSA
COIL TEMP
SENSOR
T3 Coil
Sensor
Alarm
A1A
A1A
AUX1
SENSOR
AUX1
Sensor
Alarm
A2A
A2A
AUX2
SENSOR
AUX2
Sensor
Alarm
A3A
A3A
AUX3
SENSOR
AUX3
Sensor
Alarm