Hanbell RC2-100AF, Manual

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PROBLEMS PROBABILITY CAUSES REMEDY / CORRECTIVE ACTION
Compressor starting
failure or Y-
Δ starter
shifting failure
Slide valve piston unable to go back to its lowest % original position.
Check if the unloading SV is energized once the
compressor shut down.
Unload the compressor before shot down.
Voltage incorrect. Check the power supply
Voltage drop too big when starting the compressor or magnetic
contactor failure or phase failure.
Check the power supply and the contactor.
Motor broken down Change the motor
Motor thermister sensor trip.
See “sudden trip of motor sensor” above
Incorrect supply power connection. Check and re-connect
Y-
Δ timer failure.
Check or replace.
Discharge or suction stop valve closed. Open the stop valve
Improper connection between node terminals of Y-
Δ wiring.
Check and re-connect the wiring
Rotor locked Check and repair
Earth fault Check and repair
Protection device trip Check
Abnormal vibration
and noise of
compressor
Damaged bearings. Change bearing.
Phenomenon of liquid compression. Adjust proper suction superheat
Friction between rotors or between rotor and compression chamber. Change screw rotors or/and compression chamber.
Insufficient lubrication oil.
Check the oil level of the compressor if enough, add
some oil if necessary.
Loosen internal parts.
Dismantle the compressor and change the damaged
parts.
Electromagnetic sound of the solenoid valve. Check
System harmonic vibration caused by improper piping system.
Check the system piping and if possible improve it
using copper pipe.
External debris fallen into the compressor.
Dismantle the compressor and check the extent of the
damage.
Friction between slide valve and rotors.
Dismantle the compressor and change the damaged
parts.
Motor rotor rotates imbalance. Check and repair.
Compressor does not
run
Motor line open Check
Tripped overload Check the electrical connection
Screw rotors seized
Replace screw rotors, bearings etc….
Motor broken Change motor.
High discharge
temperature
Insufficient refrigerant.
Check for leaks. Charge additional refrigerant and
adjust suction superheat less than 10°K
Condenser problem of bad heat exchange. Check and clean condenser
Refrigerant overcharge. Reduce the refrigerant charge
Air / moisture in the refrigerant system Recover and purify refrigerant and vacuum system
Improper expansion valve. Check and adjust proper suction super heat
Insufficient lubrication oil. Check the oil level and add oil.
Damaged bearings.
Stop the compressor and change the bearings and
other damaged parts.
Improper Vi value. Change the slide valve.
No system additional cooling (Liquid injection or oil cooler)
Install additional system cooling (liquid injection or oil
cooling or both base on working condition limitation)