Pressure Equalizing Control - Daikin VRV - WII Service Manual

Startup Control
4.3

Pressure Equalizing Control

This pressure equalization control is used to equalize the pressure of discharge piping and suction
piping in order to reduce refrigerant passing noise when changing over the BS units.
[Starting conditions]
The temperature control of indoor units with thermostat ON does not match up with the state of the
BS unit changeover valve to which the indoor units are connected.
Parts name
Compressor
4 way valve (Main)
4 way valve (for heat exchanger)
Main electronic expansion valve
Sub-cooling electronic expansion valve
Hot gas bypass solenoid valve
Water heat exch. oil return solenoid valve
Receiver gas charging solenoid valve
Receiver gas
Non-operation unit liquid pipe stop
Indoor cooling unit fan
Indoor cooling unit
Indoor heating unit fan
Indoor heating unit expansion valve
Cooling
BS 20RH
Heating
BS 20RT
Ending condition
64
Electrical
Symbol
symbol
— (M1C)
20S1 (Y5S)
20S2 (Y7S)
EV1 (Y1E)
EV3 (Y3E)
SVP (Y1S)
SVE (Y2S)
SVL (Y3S)
SVG (Y4S)
SVSL (Y6S)
— (M1, 2F)
EV (Y1E)
— (M1, 2F)
EV (Y1E)
20RH (Y3S)
20RT (Y1S)
Pressure equalization control
74Hz
OFF
OFF
2000 pulse
0 pulse
ON
OFF
OFF
OFF
ON
No instruction
No instruction
OFF
192 pulse
No instruction
No instruction
OFF
Max. 5 min.
SiUS30-604
Function