Adjustment During Operation - Panasonic OCU-CR1000VF8 Operating Instructions And Installation Instructions

Control Functions
(6) Inverter abnormality
Compressor is stopped when abnormal operations which are indicated as section "About alarms" occurred.
Refer to Inverter anomaly of section "About alarm" for detail.
(7) Inverter communication abnormality
When the inverter V1000 or A1000 cannot receive data from the CR2-EN-PCB, compressor operation stops with
error display.
For the method of resuming (resetting) compressor operation, refer to the "Description of Abnormality Alarm" in
"About Alarms"
Defrosting Control
Operates defrosting control according to instructions from the controller. During the defrosting operation, the
defrost (green) LED lights up and the compressor operation is stopped.

Adjustment during Operation

Avoiding Short Cycle Operations
Short cycle operation (frequent start/stop operation) causes excessive oil carry-over during starting and causes
insufficient lubrication.
Adjust operation cycle to avoid short cycle operation. (Adjust ON-OFF cycle to be 10 minutes or longer.)
The main cause of short cycle operation is inappropriate pressure setting on CRD2-EN-PCB, suction filter clogging,
and unbalance of cooling capacity and load.
When a cooling coil is used, incorrect attachment position of the compartment temperature sensor (cold air-blow
directly hit the sensor) would become a problem in addition to the above. Review the sensor position.
Checking the Operation Condition of the Refrigeration Unit
(1) Check abnormal vibration of the refrigeration unit and piping.
(2) Check insufficient or excessive charging of refrigerant. (Check gas cooler outlet temperature and high pressure)
(3) Check if the compressor oil quantity is appropriate. (Check with the digital display on the control PCB)
It normally takes several hours to several days for the oil level to stabilize, therefore requiring monitoring.
Adjust the oil quantity if it is insufficient or excessive.
[Method of checking oil level]
Set the rotary switch (knob) on the control PCB to "Operation mode," and turn ON DIP switch 13-7 to enter
the oil level confirmation mode.
<Digital display example>
For details about checking the oil level, refer to the "Oil Level Control and Oil Addition Assessment Criteria"
of "Oil Level Control Method."
(4) Check if the set value of the expansion valve (electronic expansion valve) and thermostat is appropriate.
(5) Check whether or not liquid return operation is permitted. (Check superheat of suction gas temperature)
Upper limit
Intermediate
Lower limit
EN - 36