McQuay MDB075B, Manual

Page: 105 / 163

104
High Suction Pressure
Low Suction Pressure
Noisy Operation
High Suction
Pressure
Excessive Fresh Air Intake
Evaporator
Air Inlet
Temperature
Insufficient Duct Insulation
Defective Compressor Valve
Reduce The Fresh Air Intake
Reinforce The Duct Insulation
Change Or Repair The Compressor
Low
Overcharged Refrigerant Purge The Refrigerant
Low Suction Pressure
Clogged Air Filter
Evaporator
Air Inlet
Temperature
Evaporator
Air Flow
Restricted Duct
Low Fan Speed
Short Cycling
Faulty Thermostat
Restricted Liquid LIne And
Suction Line
Low Discharge Pressure
Clean The Air Filter
Remove The Restriction
Adjust The Fan Speed
Remove Obstacles To Air Circulation
Repair Or Replace If Necessary
Restricted
Low
Low Refrigerant Charge Add Refrigerant
See "Low Discharge Pressure"
Remove The Restriction
Noisy Operation
Unremoved Shipping Bolt(s)
Evaporator
Fan
Compressor
Overcharged Refrigerant
Low Suction Pressure
Worn Compressor Parts
Knocking Runner
Worn Bearing
Refrigerant Short Charge
Remove The Bolt(s)
Purge The Refrigerant
See "Low Suction Pressure"
Replace Or Repair The Compressor
Fix The Runner Or Casing Properly
Noisy
Partially Clogged Clean The Dryer
Add Refrigerant
Change The Bearing
Liquid Line
Shipping
Bolt(s)
Liquid
Refrigerant
Backing Up
Noisy
Noisy
Inadequate Duct Work
Loose Fixed Screws Tighten All Fixed Screws
Check Flexible Ducts
Noisy
Strainer
Whistling