66 Chapter 7 System Operation And Maintenance
Liebert. PEX+Series Precision Air Conditioner User Manual
Components
Inspection items
Compressor
No leakage
Check for noise and observe vibration condition
Check and fix connectors
Air cooled condenser
Cleanliness of condenser fins
Fan base is rigid.
Check if vibration absorbing cushion is aging or damaged
Check if SPD board(if any) is working, and check once a week in
thunderstorm seasons.
Refrigerant pipes have suitable support
Check and fix connectors
Water cooled condenser
Clean pipe system
Check the function of ball valve
Check if the water system leaks
Cooling system
Check the refrigerant pipes that must have support bracket and should
not be closed to wall, floor or fixed frames with vibrations.
Check the moisture condition in system through sight glass
Check HGBP valve
Check thermal expansion valve
Check if the system needs to be added with refrigerants through sight
glass
Heating syste
Check the operation of reheat system components
Check and fix connectors
Infrared humidifier
Check if water pan drainage is clogged
Check the lamp of humidifier
Check water pan for mineral deposits
Check and fix connectors
Electric control part
Check and fix connectors
7.3 Self-diagnosis Function
The Icom controller features a diagnostic function that enables you to turn on/off the components in site manually so
as to check their functionality.
7.4 Electrical Connection Inspection
The inspection items include:
1. Conduct overall electrical insulation test: find out the unqualified contacts and handle them. Note to disconnect the
fuses or MCBs of the control part during the test lest the high voltage should damage the control components.
2. Check the contactors before power-on and make sure the contactors can act freely without obstruction.
3. Clean the electric and control elements of dust with brush or dry compressed air.
4. Check the closing of contactors for arcs or signs of burning. Replace the contactor if necessary.
5. Fasten all the electric connection terminals.
6. Check that the sockets and plugs are in good condition. Replace those loosened ones.
7. If the power cables are damaged, to avoid damage, the cables must be replaced by professional personnel.
7.5 Control Component Appearance Inspection
Carry out visual inspection and simple function test by referring to the following items:
1. Visually inspect the power transformers and isolation transformers, and test the output voltage (of the indoor unit
and outdoor condenser).
2. Check that there is no signs of aging on the control interface board, control board, temperature and humidity sensor
board and fuse board.
3. Clean the electric control elements and control board of dust and dirt with brush and electronic dust removing agent.
4. Check and fasten the I/O ports at the control interface board, including the connection between control board and
control interface board, as well as between the temperature/humidity sensor board and the interface board.
