4–33 T-362
Component Monitor Unit
Troubleshooting Alarm is display only; the alarm may clear itself during operation.
Corrective Action If alarm remains active or is repetitive, replace compressor at next available
opportunity.
AL18 Discharge Pressure High
Cause: Discharge pressure is over the maximum for 10 minutes within the last hour.
Component Restrictions in the refrigeration system.
Troubleshooting Ensure Liquid Line Service Valve is fully open.
Corrective Action Open Liquid Line Service Valve as needed.
Component Filter Drier
Troubleshooting Check the filter drier. If it is iced up or very cold, it indicates that the filter drier
needs replacement.
Corrective Action Replace the filter drier if needed. See Filter Drier Service Section 7.14.
Component Condenser Fan
Troubleshooting Check Condenser Fan for proper operation.
Corrective Action Correct as required.
Component Discharge Pressure Transducer (DPT)
Troubleshooting Confirm accurate DPT pressure readings. See Manifold Gauge Set Section 7.2.
Corrective Action Replace DPT if defective.
Component Non-condensables in the refrigeration system.
Troubleshooting With the unit off, allow system to stabilize to ambient temperature.
Check system pressure against Pressure Temperature Chart. See Table 7–5,
Table 7–6.
Corrective Action Correct as required. See Refrigerant Charge Section 7.7.1.
Component Refrigerant
Troubleshooting Check refrigerant level.
Corrective Action Correct as required. See Refrigerant Charge Section 7.7.1.
AL19 Discharge Temperature High
Cause: Discharge temperature exceeds 135°C (275°F) for 10 minutes within the last hour.
Component Restrictions in the refrigeration system.
Troubleshooting Ensure the Discharge Service Valve is fully open.
Corrective Action Open the Discharge Service Valve as needed.
Troubleshooting Check the unit for air flow restrictions.
Corrective Action Clean or remove any debris from coils.
Component Non-condensables in the refrigeration system.
Troubleshooting With the unit off allow system to stabilize to ambient temperature.
Check system pressure against Pressure Temperature Chart. See Table 7–5,
Table 7–6.
Corrective Action Correct as required. See Refrigerant Charge Section 7.7.1.
Component Additional Alarms such as AL16, AL24.
Table 4–5 Alarm Indications and Descriptions
To Next Page
Loading...
