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Diagnosis: Troubleshooting, Warnings and Alarm Codes
236
31
Low Pressure Cut Out
• If Low pressure switch is mounted.
• The switch is OPEN.
• If pressure transducer is mounted.
• The suction pressure has been measured below
-0,27BarR and has not yet increased above
+0,38BarR.
• Indicates:
• Low refrigerant charge.
• Refrigeration system restriction at filter drier or
expansion valve.
• Defective low pressure cutout switch.
• Defective low pressure transmitter.
• Check discharge and suction pressure gauge
readings:
• If refrigerant pressures are low, check for a
restriction and leak check the refrigeration
system.
• If refrigerant pressures are high, check for a
high refrigerant charge (see below).
• Check for a restriction:
• Check for frost on downstream side of the
filter drier.
• Check for high evaporator superheat using
supply air sensor temperature readings in
Data menu or a frost pattern on expansion
valve side of the evaporator coil. A large
temperature difference between the left
hand and right hand supply air sensors
indicates a possible evaporator restriction or
incorrect superheat.
• If Low pressure switch is mounted
• Check low pressure cutout switch wiring.
• Measure the voltage across the switch,
located at J9 pin 6 and pin 5.
- Switch closed (normal) voltage is 0VDC.
- Switch open (LPCO) voltage is approx.
12VDC.
• Replace switch.
• If pressure transducer is mounted,
• Measure the transducer supply voltage at J1
pin 8 related to J1 pin 9 (GND). Expects to
be approx. 12VDC.
• Measure the transducer output voltage at J1
pin 7 related to J1 pin 9 (GND). Expects to
be above 0,5VDC (0BarR = 0,8VDC)
Alarm Codes, Descriptions and Corrective Actions (Continued)
Code
Description
Corrective Action
Summary of Contents for 098203
Page 2: ......
Page 3: ...MAGNUM TK 60275 4 MM Rev 3 08 15 Copyright 2012 Ingersoll Rand EMEIA Printed in Ireland...
Page 193: ...Refrigeration Maintenance 191 Figure 163 Filter Drier...
Page 200: ...Refrigeration Maintenance 198 Figure 169 Receiver Tank Figure 170 Water Cooled Condenser Tank...
Page 257: ...255 Schematic Diagram RELEASED 19 Sep 2013...
Page 258: ...256 Wiring Diagram Page 1 of 2 RELEASED 19 Sep 2013...
Page 259: ...257 Wiring Diagram Page 2 of 2 RELEASED 19 Sep 2013...
Page 263: ......