Refrigerant Flow Rate Control - Daikin RTSQ20PY1 Service Manual

Normal Operation
6.7

Refrigerant Flow Rate Control

Recovery of Refrigerant
When the indoor unit operates at low load, the solenoid valves (Y1S and Y4S) will be energized
to recover excess refrigerant to the refrigerant regulator.
Discharge of Refrigerant
When the indoor unit operates at high load, the solenoid valve (Y7S) will be energized to
discharge refrigerant from the refrigerant regulator.
Pressure Regulating Valve (Refrigerant Regulator)
When all solenoid valves (Y1S, Y4S, and Y7S) are deenergized, a closed circuit will be set up.
To avoid that, relieve pressure raised by the refrigerant regulator to the liquid refrigerant piping
side.
97
Subcooling
heat
exchanger
Liquid pipe
Strainer
Gauge port
Pressure regulating valve
Capillary tube
(check valve type)
Equalizing pipe
High pressure sensor
Solenoid
valve
Gauge port
Suction gas pipe
Subcooling
heat
exchanger
Liquid pipe
Strainer
Gauge port
Pressure regulating valve
Capillary tube
(check valve type)
Equalizing pipe
High pressure sensor
Solenoid
valve
Gauge port
Suction gas pipe
Electronic
Filter
expansion
Electronic
valve
expansion
Solenoid valve
valve
Check valve
SV
Four way valve
Filter
Check valve
Filter
(Y4S)
S1PH
High pressure
Check valve
Filter
switch
SV
Solenoid valve
Compressor
Capillary tube
INV
Solenoid valve
S2NPL
Low pressure (Y7S)
Filter sensor
Electronic
Filter
expansion
Electronic
valve
expansion
Solenoid valve
valve
Check valve
SV
Four way valve
Filter
Check valve
Filter
(Y4S)
S1PH
High pressure
Check valve
Filter
switch
SV
Solenoid valve
Compressor
Capillary tube
INV
Solenoid valve
S2NPL
Low pressure (Y7S)
Filter sensor
SiBE31-801_C
Right
Heat exchanger
Pressure regulating
Solenoid
valve (absolute
valve
pressure type)
Check
Strainer
valve
Refrigerant regulator
Filter Filter
Solenoid valve
(Y1S)
Capillary tube
Right
Heat exchanger
Pressure regulating
Solenoid
valve (absolute
valve
pressure type)
Check
Strainer
valve
Refrigerant regulator
Filter Filter
Solenoid valve
(Y1S)
Capillary tube
Function