108 StarCool Alarm Codes And Actions

108  Tsup 2 invalid
Description Supply Air Temperature Sensor 2 Invalid
Cause Indication of defective supply air temperature sensor or its measuring circuitry or sensor not mounted correctly in unit
Trouble
shooting
Possible causes:

  • Active alarms AL 106, AL 107 or AL 901 (if CIM5 software)
  • Temperature sensor reading is out of valid range: -60°C (-76°F) or above +140°C (284°F).
  • Difference between Tsup1 and Tsup2 is larger than 1°C: 1°C difference for more than 30 min. or up to 10°C difference in more than 3 min.

Trouble shooting:

  1. Try to correct the error by uploading the latest software version to the controller.
  2. Check that both sensors, Tsup1 and Tsup2 are mounted correct in the supply air pockets.
  3. If AL 901 is active, see trouble shooting for AL 901
  4. Disconnect the sensor cable for sensor Tsup2 from the connector on the main controller, according to the wiring schematics inside in the control cabinet.
  5. Measure the resistance between the two wires.

a) If the resistance is out of range, see “30.2 Temperature Sensor [°C] - Resistance Table” p. 185, the temperature sensor and cable are defective and should be replaced.

b) If the resistance is within range, perform main controller check “16.1 Trouble shooting for Star Cool main controller” p. 60 before replacing main controller.
Criteria Value is below alarm limit -60°C (-76°F) or above +140°C (284°F) or difference between Tsup1 and Tsup2 is more than (>) 1°C for 30 min. or up to 10°C difference. Value invalid for 30 sec. for alarm activation.