Vertiv Liebert CRV Plus - Page 55

Vertiv | Liebert CRV+ | User Manual 45
Since the single direction valve is a standard configuration of the unit, the vacuuming mode should be
enabled (open the solenoid valve in liquid pipe), when performing nitrogen pressure dwelling or
discharging the nitrogen after the pressure dwelling.
2. Installing the connection pipes
 Check if the equivalent length of the single-way pipe of the air cooled unit exceeds 30m
 Check whether the extension kit and oil trap are installed
 Confirm if the corresponding refrigerant oil needs to be re-filled
Refill the
oil from the needle valve that is behind the expansion valve.
 Check if the rated voltage of the solenoid valve on the liquid pipe meets the requirements
 Check the relative positions between the condenser and the outdoor unit. If the condenser is
higher than the outdoor unit, the liquid pipe should be at a greater height than the “U” bend of the
condenser coil.
3. Vacuuming
 Open all the ball valves and solenoid valves in the refrigerant pipes of the air cooled unit;
Enable t
he vacuuming mode, and open the solenoid valve in liquid pipes.
 Vacuum from both the high and low pressure locations according to the indications of the labels;
Requirements: The vacuum rate of the system should be below 20Pa (absolute pressure); Vacuum
pressure dwell time is 4h, while the pressure should not be increased, and the sight glass indicates the
dry status.
Inspection of Auxiliary Parts and Cables
1. Check if the drainage is normal
2. Check the electric circuits:
 Fasten all the electrical connections, and make sure that there is no short circuit and open circuit
and the insulation is good;
Check the main power supply voltage of the unit.