Emerson Liebert Deluxe System/3 DH - Manual (Page 74)

Troubleshooting
66
Refrigerant flooding
Defective or improperly set
expansion valve
Increase superheat or replace valve
Evaporator fan motor or belt Correct problem or replace fan motor and/or belts.
Low condensing pressure Check head pressure control device
Slipping belts Inspect and adjust
Blown valve plate or
cylinder head in comp.
Liquid refrigerant floodback or
flooded start
See Symptom: Flooding
Low compressor
capacity or inability to
pull down system
Blown valve plate or cylinder
head gasket.
Replace gaskets. Retorque cylinder head bolts to
compressor manufacturer's specs.
Leaky valve plate or worn valve
seats
Replace valve plate assembly
Leaky suction valves
Pump down, remove cylinder head examine valve and valve
seats. Replace if necessary
Broken connecting rods or
pistons
Replace compressor.
Leaking liquid line solenoid valve
or dirt in valve
Replace valve if clean; clean out valve if dirty.
Compressor noisy
Slugging due to floodback of
refrigerant
See Symptom: Flooding
Bearings wiped because of loss
of oil
See Oil Pressure. Check for defective oil failure control.
Loose compressor or piping
support
Tighten clamps.
Broken connecting rods, valves
or other running gear
Replace compressor
Pipe rattle Loose pipe connections Check pipe connections
Compressor running hot
Blown valve plate or cylinder
head gasket
See Symptom: Blown Valve Plate
Broken suction or discharge
valve
Replace valves and valve plate, if necessary.
Compression ratio too high
Check setting of high and low pressure switches. Check
condenser-- is it plugged? Check that all evaporator and
condenser fans are operating properly.
Excessive blow-by into
crankcase -work rings, valves, or
blown gasket
Replace gasket, valve plate, or compressor
Compressor cycles
intermittently
Low-pressure switch erratic in
operation
Check tubing to switch to see if clogged or crimped Check
for proper switch operation
Insufficient refrigerant in system Check for leaks, fix, and add refrigerant
Suction service valve closed Open valve.
Insufficient water flowing through
condenser or clogged
condenser, or dirty air cooled
condenser coils
Adjust water regulating valve to condenser. Clean
condenser.
Discharge service valve not fully
open
Open valve
Table 23 Compressor and refrigeration system troubleshooting (continued)
Symptom Possible Cause Check or Remedy