Low Suction Superheat
refrigeration
Description
Compressor suction superheat is less than 5b0C (9b0F) for more than two minutes, and the unit shuts down and alarms.
Activation Conditions
Alarms 00127 Check Suction Temp Sensor and/or 00131 Check Evap Temp Sensor are not active and Compressor Suction Superheat (Compressor Suction Temperature (CST) minus saturated temperature for Compressor Suction Pressure (CSP)) is less than 5°C (9°F) for more than two minutes.
Unit Behavior
Shutdown and alarm.
Reset Conditions
Auto reset after 15 minutes, or alarm may be manually reset using the display mounted keys or by turning the unit off, then back on again.
Corrective Actions
1. Check System Pressures: Install manifold gauge set and check and compare compressor discharge, suction and evaporator outlet pressure to the Unit Data readings. Refer to Section 8.9.10. 2. Check Evaporator Section: Check return air bulkhead, air chute and the evaporator coil (for cleanliness and airflow). Refer to Section 9.3.12. 3. Perform Pretrip Check: Clear Active Alarm list, then run Pretrip and check for any new alarms. Any active alarms must be corrected and cleared before proceeding. 4. Check Expansion Valve (EVXV): Refer to Section 8.9.7.