【 Weak current College 】 chiller eight maintenance work

1. check chiller unit runs, the lookup operation records and set alarms
1.1 check unit operation records, analysis of the last warning content
1.2 check alarm possible occurrence points
1.3 records unit current problems

2. check unit external circumstances
2.1 check unit appearance, corrosion and contamination
The unit external 2.2 checking interface, the leakage of solder joints
2.3 check compressor, motor and other parts base fixed situations
2.4 check and fastening units of all moving parts, the system fixed pipeline components. Including foot bolts and
For screws, etc.
2.5 check unit pressure hose fitting connection is reliable, check compressor base fixed situations
2.6 expansion valve fixed reliability and temperature sensor, balance pipe fixed reliable
2.7 check evaporator, condenser connect fixed and reliable

3. check unit condenser and evaporator of pollution
3.1 check frozen water evaporator case scaling
3.2 testing water temperature difference between the side and the refrigerant
3.3 evaporator water system contamination for evaporator sewage or recommended chemical cleaning

4. check system and lubrication system check compressor lubricant condition 4.1 oil quality and, if necessary, the lubricating oil
4.2 clean or replace oil filter
4.3 clean compressor oil pan
4.4 check and clean the compressor suction strainer
4.5 checking system drying, drying filter replacement

5. check compressor and motor insulation resistance value and current value
5.1 measurement value compressor motor insulation
5.2 measurement pump motor insulation value
5.3 after running compressor, pump check voltage, three-phase current value

6. check the electrical wiring in the control box, the operational reliability and should be avoided because of exposure to vibration, in run
Abrasion damage in
6.1 check compressor terminal box Terminal fixed reliable within
6.2 check pumps reliable wiring
6.3 check control box incircuit various contacts fixed reliable

7. check all electrical wiring contactors, solenoid valve, electrical components
7.1 check and clean the compressor contactor, pump contactor contacts reliability, no obvious Burns
7.2 check the solenoid valve coil unit in good condition and action correct, if necessary, for maintenance and replacement

8. check chiller unit calibration of the sensor and instrument, pressure switch setting value
Checking in and out of the water temperature 8.1 sensors, the outdoor temperature sensor, flow switch
8.2 verification of high and low pressure sensor, pressure sensor values
8.3 checksum table, low table under high pressure, oil pressure table values
8.4 check screw compressor spray liquid temperature sensor
8.5 check reliability of high-voltage switch.