Vertiv Liebert CRV Plus - Page 57

Vertiv | Liebert CRV+ | User Manual 47
The unit should first be dynamically charged from the needle valve. If some units cannot be
charged during the later charging stage, it can be charged from the suction port, but monitor
the charging speed. The unit uses the high pressure chamber compressor that can be easily
damaged if the charging is made through the suction port;
Charge the unit respectively at 50%, 70% and 100% compressor outputs until there is no
bubble;
The unit may be stopped due to “low superheat” if the charging speed is high and the
superheat is below 10 ℃( auto reset after 3min), and after the alarm reset, manually start
the compressor;
In manual control mode, the pump will not be opened automatically, so for the unit with pump,
open the pump according to the condensation conditions.
Record the running parameters of the cooling system according to the requirements of CRV+ Air Cooled
Air Conditioner Startup and Commissioning Report.
Record the parameters Operating Instructions
1. Start the manual mode
Start up from the panel – Enter level 2 password – Set the system – Manual Mode – Manual Mode
Enabled – Set to “Y”
2. Start vacuum mode
Enable Manual Mode－Vacuum mode－Set to “Y”
1) Close the transformer circuit breaker;
2) Ignore the “Fan/Power Failure” alarm after startup;
3) If the vacuuming starts before the vacuuming mode is started, “low pressure sensor fault” alarm will
occur after startup, and then ignore this alarm.
3. Manually start / stop each component
Enable Manual Mode－Start / stop the output of corresponding component－The output percentage
value of the compressor and fan can be adjusted after they are started up
1) Output percentage value of the compressor cannot be adjusted until the compressor has started up
for about 5min (i.e., the soft start is over);
2) After the compressor is off (includes manual turn-off and unit shutdown), the compressor will be in
soft shutdown status (in manual mode - the soft shutdown status is displayed as “Y”), but still keeps
derated speed output. After the soft shutdown phase is ended (about 5-10min), the compressor is off.
In order to ensure the reliability of the compressor, avoid directly turning off the circuit breaker of the
compressor.
Refer to the Refrigerant refill and charging section in the user manual for the calculations.