Refrigeration System Diagnostics; Refrigeration System Checklists; Discharge Pressure High Checklist; Discharge Pressure Low Checklist - Manitowoc Multiplex N2Fusion Service Manual

Troubleshooting

Refrigeration System Diagnostics

REFRIGERATION SYSTEM CHECKLISTS

Installation/Visual Inspection Checklist
Inadequate Clearances
• Check all clearances, on sides and back.
Sides
Back
Front
Condenser is dirty
• Clean the condenser

DISCHARGE PRESSURE HIGH CHECKLIST

Air Condenser
• Dirty condenser fins
• High inlet air temperature
• Condenser discharge air recirculation
• Defective fan motor
Other
• Overcharged
• Non-condensable (air) in system
• Wrong type of refrigerant
• Non-OEM components in system
• High side refrigerant lines/component restricted

DISCHARGE PRESSURE LOW CHECKLIST

• Undercharged
• Wrong type of refrigerant
• Non-OEM components in system
42

SUCTION PRESSURE HIGH CHECKLIST

Improper Installation
•
Discharge Pressure
•
0" (0 cm)
Improper Refrigerant Charge
3" (76mm)
•
30" (76 cm)
•
•
Components
•
Other
•

SUCTION PRESSURE LOW CHECKLIST

Improper Installation
•
Discharge Pressure
•
Improper Refrigerant Charge
•
•
Other
•
•
•
Refer to "Installation/Visual Inspection Checklist"
Discharge pressure is too high and is affecting suction
pressure
Overcharged (also see "Freeze Cycle Discharge Pressure
High Checklist" )
Wrong type of refrigerant
Non condensible in system
Defective compressor
Non-OEM components in system
Refer to "Installation/Visual Inspection Checklist"
Discharge pressure is too low and is affecting low side –
refer to "Freeze Cycle Discharge Pressure Low Checklist"
Undercharged
Wrong type of refrigerant
Non-OEM components in system
Restricted/plugged liquid line drier
Restricted/plugged tubing in suction side or liquid line
of refrigeration system
Part Number 020007115 06/27/2019
Section 5