22
Figure 4-5
4.10 Preliminary Running
In order to lubricate the compressor movement parts, the compressor should be operated at least 3 seconds
within 15min after refrigerant charged. Check the following items:
1)
To check whether abnormal sound or abnormal tube vibration occurs.
2)
To check whether refrigerant leaks from the connection part.
3)
To check the cooling effect.
4.11 Start Compressor with Balanced Pressure
The OFF cycle setting of compressor should be at least 3 minutes which is the period to balance the high
side and low side pressure of system. Especially for single phase models, starting the compressor with
balanced pressure should be always followed.
4.12 Servicing Scroll Compressors
4.12.1 Compressor Functional Check
The following procedures should be followed to determine if the compressor is functioning properly:
1)
Voltage of the unit should be measured and verified as correct.
2)
An evaluation of the electrical system should be performed next. The motor should be checked by using
continuity and short to ground testing. The internal motor protector should be given time to reset if a
continuity break is found in the motor windings. External breakers and associated wiring should be
checked.
3)
Operation of indoor and outdoor fan/blower should be checked and verified as correct.
4)
Check the refrigerant charge levels by connecting service gauges to the suction and liquid service valves
and then turning on the compressor. Correlate the operating pressures to the system manufacturer
specifications for the existing conditions under which the unit is operating.
5
）
On heat pump, check that the reversing valve is operating properly and verify that compressor current is
within published compressor specifications at the proper operating conditions. If there is a significant
