Daikin VRV II RXYQ8MY1K Service Manual page 78

Si39-502A
3.6.3 Stopping Operation of Slave Units During Master Unit is in Operation
with Multi-Outdoor-Unit System
While the master unit is in operation, this mode is used to set the refrigerant flow rate to a required level using a slave
unit in the stopped mode.
In cooling operation: The system operates in Mode A or Mode B listed in the table below.
Actuator
Compressor
Outdoor unit fan
Four way valve
Main motorized valve (EV1)
Subcooling motorized valve (EV2)
Hot gas bypass valve (SVP)
Receiver gas discharging valve
(SVG)
Non-operating unit liquid pipe stop
valve (SVSL)
Mode transition conditions
Ending conditions
∗ Mode A or B operation

Mode A : Operating unit collects refrigerant.


Mode B : Stopping unit storage refrigerant.
The changeover operation for mode A and B is performed for the reason that the required refrigerant amount varies
depending on the indoor unit operation capacity.
In heating operation: The system operates with following Mode.
Actuator
Compressor
Outdoor unit fan
Four way valve
Main motorized valve (EV1)
Subcooling motorized valve (EV2)
Hot gas bypass valve (SVP)
Receiver gas discharging valve
(SVG)
Non-operating unit liquid pipe stop
valve (SVSL)
Ending conditions
Function
Mode-A operation
OFF
STEP4
OFF
150 pls to 300 pls
0 pls
ON
OFF
OFF
To Mode B when Tc-Tl >0.27×(Tc - Ta) +6
Slave units are required to operate.
Operating Stopping
unit unit
OFF
OFF
ON
0 pls
0 pls
OFF
OFF
OFF
Slave units are required to operate.
Mode-B operation
OFF
OFF
Holds ON
0 pls
0 pls
ON
OFF
ON
To Mode A when gas shortage signal
is sent from indoor unit
Operation
Special Control
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