Vertiv Liebert CR012 - Preparations for Startup; Startup Inspection

Liebert CR012 Precision Air Conditioning User Manual
Chapter 2 Installation 31
Items
Inspection contents
Results
indoor and outdoor units are normal, and whether the power supply cables are well connected and
whether each functional circuit breaker and contactor are reliably connected.
SPD (if
installed)
The SPD module should not be loosened, and the alarm terminals should be correctly connected.
Controller
All the control wirings are reliable.
Pipes
The pipes are connected and supported reliably; The extension kit (single direction valve and
solenoid valve) is installed in the right positions and directions; There is no exposed copper pipe and
the thermal insulation cotton is well attached.
2.5.2 Preparations for Startup
In this section, the following sections would be explained in brief to help users understand the basics of the
Commissioning process, but do remember that the commissioning will be done by authorized engineers or trained
personnel of Vertiv only.
Inspection of Pipes
1. Checking the nitrogen pressure dwelling of the cooling pipes of the air-cooled unit:
Requirements: Use high pressure nitrogen to dwell pressure. Dwell pressure is 40 bar, the dwell time ≥ 24h and the
pressure values before and after the dwell will be the same.
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
1. Check if the equivalent length of the single-way pipe of the air-cooled unit exceeds 30m
2. Check whether the extension kit and oil trap are installed
3. Confirm if the corresponding refrigerant oil needs to be re-filled
Refill the oil from the needle valve that is behind the expansion valve.
4. Check if the rated voltage of the solenoid valve on the liquid pipe meets the requirements
5. 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 the 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.
4. 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.
2.5.3 Startup Inspection
1. Open the corresponding circuit breaker of each component of the unit, close the general circuit breaker and the
transformer circuit breaker, and check the control voltage;
2. Check the indoor fan:
Close the fan circuit breaker; manually set the 75% output to check the fan running current.