Daikin VRV II REYQ10MY1B, Service Manual

Page: 89 / 309

Special Control Si39-306
78 Function
3.7.2 Stopping Operation of Slave Units During Master Unit is in Operation
with Multi-Outdoor-Unit System
This operation is used to make adjustments of required refrigerant amount with non-operating
slave units while the master unit is in operation.
In cooling operation : The system operates in mode A or mode B listed in the table below.
In heating operation or simultaneously in cooling / heating operation :
The system operates in mode A or mode B listed in the table below.
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.
*
Actuators are based on REYQ16M.
Actuator Mode-A operation Mode-B operation
Compressor OFF OFF
Outdoor unit fan STEP4 OFF
Four way valve 1 OFF OFF
Four way valve 2 OFF OFF
Main motorized valve (EV1) 150 pls to 300 pls 0 pls
Sub motorized valve (EV2) 0 pls 0 pls
Sub-cooling motorized valve (EV3)
Built-in compressor discharge pipe
temperature control Built-in compressor discharge pipe
temperature control
Hot gas bypass valve (SVP) ON ON
Oil equalization valve (SVO) OFF OFF
Receiver gas charging valve (SVL) OFF OFF
Receiver gas discharge valve (SVG) OFF OFF
Discharge pipe stop valve (SVR) OFF OFF
Non-operating unit liquid pipe stop
valve (SVSL)
OFF ON
High pressure gas pipe pressure
reduction valve (SVC)
ON ON
Mode transition conditions
To Mode B when Tc-Tl
>0.27×(Tc - Ta) +6
To Mode A when gas shortage signal is
sent from indoor unit
Ending conditions Slave units are required to operate.
Actuator Mode-A operation Mode-B operation
Compressor OFF OFF
Outdoor unit fan
Incorporated INVFIN temperature
control Incorporated INVFIN temperature
control
Four way valve 1 ON ON
Four way valve 2 ON ON
Main motorized valve (EV1) 0 pls 0 pls
Sub motorized valve (EV2) 0 pls 0 pls
Sub-cooling motorized valve (EV3)
Built-in compressor discharge pipe
temperature control Built-in compressor discharge pipe
temperature control
Hot gas bypass valve (SVP) High/Low pressure protection control High/Low pressure protection control
Oil equalization valve (SVO) OFF OFF
Receiver gas charging valve (SVL) ON OFF
Receiver gas discharge valve (SVG) OFF OFF
Discharge pipe stop valve (SVR) ON ON
Non-operating unit liquid pipe stop
valve (SVSL)
In case of EV3
≠
0, this valve turns ON. In case of EV3
≠
0, this valve turns ON.
High pressure gas pipe pressure
reduction valve (SVC)
OFF OFF
Mode transition conditions
To mode B when Tc - mean temperature
of indoor unit liquid pipes > 10 Motorized valve of outdoor unit in heat
exchange mode fully opens.
Ending conditions Slave units are required to operate.
Mode A : Operating unit collects refrigerant.
Mode B : Stopping unit storage refrigerant.



Operating
unit
Stopping
unit
∗
Mode A or B operation