Chapter 7 Start-Up 35
Liebert.CRV Series Air Conditioner User Manual
Chapter 7 Start-Up
This chapter introduces start-up of the Liebert.CRV air conditioner, including first start-up (or after long standstill),
automatic restart, checking the refrigeration piping pressure drops, and chilled water valve of chilled water (C) units.
7.1 First Start-Up (Or After Long Standstill)
Warning
To prevent compressor damage, the crankcase(s) must be preheated for at least 4 houes before conditioner start-up (failure to
do so invalidates the guarantee).
Start the air conditioner as follows:
1. Open all valves in the refrigeration circuit according to the instruction label attached to the valve.
2. Water-cooled unit only: Open all valves in the water circuit according to the instruction label attached to the valve.
3. Ensure that the refrigerant charge is correct (see
Chapter 4 Refrigeration Connections
).
4. Using a leak detector, verify that there are no refrigerant leaks. If there are any, then repair the leak and recharge
as described in
Chapter 4 Refrigeration Connections
.
5. At least 4 hours before start-up, close the main switch and the compressor switch on the electrical panel.
In the ‘iCom’ control system factory setting the stand alone mode is standard. The stand alone mode gives the
possibility of turning on the unit simply rotating the main switch on the electric panel. The yellow LED on the iCom
case will light after turning on the unit, because of the presence of electric power.
If the LED does not light up:
Check the electric panel power supply;
Check the protection devices (e.g.: thermal switches);
Check the fuses.
6. Verify the operation of the crankcase heater.
7. Check that there are no water leakages.
8. If an external condenser or Dry cooler is installed, start it by supplying power to it.
9. Close all MCBs on the electrical panel.
10. Check the supply voltage on all phases.
11. Check the supply voltage on all phases for the external condenser or Dry cooler, if fitted.
12. Ensure that the compressor has been preheated for at least 4 hours before starting the unit.
13. Start the unit by pressing ON/OFF.
14. Check the electrical absorption of all components (see
Chapter 6 Electrical Connections
).
15. Check the electrical absorption of the external condenser/Dry cooler, if fitted.
16. Important: If the compressor makes a loud and unusual noise, it is necessary to invert the electrical connections
of the phases supplying the corresponding scroll compressor, which accepts only one direction of rotation.
17. Ensure that the fans rotate in the correct direction (see arrow on fan).
Caution: risk of contact with rotating devices.
18. Ensure that all control system settings are correct and that there are no alarms.
19. Water-cooled unit only: Verify the water flow.
20. Water-cooled unit only: For closed circuit units ensure that the water pump starts when the compressor starts.
21. Once the system is operating under load, check the various components, as follows:
Verify that the fans are operating properly.
