LT-S-(L) Technical manual
6. Poor piping causing resonance
7. Foreign objects enter the compression chamber.
Reverse time of
the rotor is too
long
1.
Stop action is not set in control logic
2.
Suction check valve stuck, fail to be closed
Discharge
temperature too
high
1. Suction superheat too high (insufficient refrigerant, expansion valve
malfunction)
2. High pressure too high(poor cooling effect, air goes into the system,
cooling water temperature too high, insufficient cooling water flow,
poor heat exchange of the condenser)
3. Compression ratio over high & no auxiliary cooling
4. Bearing damage & rotor friction
5. Oil leakage or oil level too low
6. Suction check valve piston suck and fail to open
System low
pressure alarm
1.
Insufficient refrigerant
2.
Evaporator frosts seriously and it affects heat exchange
3.
Opening of the expansion valve too small; temperature sensor failure
4.
Suction filter is blocked by ice or debris
5.
Capacity of evaporator is too small
6.
Wrong setting of the low pressure protection
System high
pressure alarm
1.
Excessive re frigerant
2.
Condenser blocked or air goes into it, causing poor heat exchange
3.
Discharge temperature too high
4.
Expansion valve blocked by ice or debris
5.
Capacity of evaporator is too small
6.
Wrong setting of the high pressure protection
Oil flow alarm
1.
Oil flow switch failure
2.
Condensing pressure fails to be established, causing insufficient oil
supply pressure differential
3.
Oil line blocked
4.
Oil line solenoid valve failure
Discharge
temperature too
low
1.
Liquid compression
2.
Temperature of returned oil is too low
3.
The opening of expansion valve on liquid line is too large
