Application Guidelines; Ompressor; Rotary Compressor; Phase Sequence And Reverse Rotation Protection - Daikin LRMYS0180AXY1 Installation, Technical And Maintenance Manual

Application Guidelines

Eensure that the refrigeration system which adopt this condensing unit MUST
integrated with pump down features (solenoid valve installed at condensing unit liquid
line outlet and energized by room thermostat). Failure to fulfill this requirement cause
liquid compression and as consequence reduce lifetime of compressor.
Table 5: Application Envelope
Operating Limits
Discharge gas temperature
Evaporator outlet superheat
Suction gas superheat at compressor inlet
Voltage supply
Phase asymmetry
Frequency
Outdoor ambient
Suction line shall be insulated to avoid:
•
High superheat during high ambient condition that can create high discharge temperature.
•
Too low superheat during low ambient condition that can condense refrigerant inside suction line.
Compressor

Rotary Compressor

The rotary compressor inside DAIKIN
condensing unit is a high-pressure dome
compressor, with 2 poles 3phase AC motor.
The pressure inside the shell of compressor
is a high (discharge) pressure and have high
temperature. Care must be taken when orientate the
power supply cables to the compressor. Never touch
the power supply cable to body of compressor, unless
heat resistant cables are used.
When replace rotary compressor, follow sequence below for
removing seal caps from the compressor:
i. Place the compressor in vertical position
ii. Remove seal cap from discharge tube and then
iii. Remove seal cap from suction tube

Phase Sequence and Reverse Rotation Protection

3 phase scroll and rotary compressor require proper phase sequence to secure correct
rotation direction and therefore compression. The phase sequence must be secured
between incoming power supply and compressor.
Three phase scroll and rotary compressor motors are designed to run only in one direction. The correct rotation of a
three-phase compressor motor depends on the connection of the three incoming phases to the unit. Correct rotation
can be determined by a drop in suction pressure and a rise in discharge pressure when the compressor is energized.
T-CU11-OCT22-0
Recommendation
0
105 C maximum for rotary compressor
0
115 C maximum for scroll compressor
Above 6K (to avoid liquid flood back)
Not more than 20K
Min: 360V, Max: 440V
+/- 2%
50Hz +/- 1%
0
Min: 20 C, Max: Refer Performance Data
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