1. Never start the Unit when no refrigerant is charged.
2. All service valves must be in the open position.
3. Check compliance between Unit and power supply.
4. Check that the crankcase heater is working.
5. Check that the fan can rotate freely.
6. Balance the HP/LP pressure.
7. Energize the Unit, it must start promptly. If the compressor does not start, check wiring conformity, voltage on terminals and sequence phase.
8. Eventual reverse rotation of a 3-phase compressor can be detected by the following phenomena: Unit doesn’t start, the compressor doesn’t build up pressure, it has abnormally high sound level and abnormally low power consumption. In such case, shut down the Unit immediately and connect the phases to their proper terminals.
9. If the rotation direction is correct, the low-pressure gauge shall show a declining pressure and the high-pressure gauge shall show an increasing pressure.

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