Daikin VRV - WII, Service Manual

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Startup Control SiUS30-604
64 Function
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 Symbol
Electrical
symbol
Pressure equalization control
Compressor — (M1C) 74Hz
4 way valve (Main) 20S1 (Y5S) OFF
4 way valve (for heat exchanger) 20S2 (Y7S) OFF
Main electronic expansion valve EV1 (Y1E) 2000 pulse
Sub-cooling electronic expansion valve EV3 (Y3E) 0 pulse
Hot gas bypass solenoid valve SVP (Y1S) ON
Water heat exch. oil return solenoid valve SVE (Y2S) OFF
Receiver gas charging solenoid valve SVL (Y3S) OFF
Receiver gas SVG (Y4S) OFF
Non-operation unit liquid pipe stop SVSL (Y6S) ON
Indoor cooling unit fan — (M1, 2F) No instruction
Indoor cooling unit EV (Y1E) No instruction
Indoor heating unit fan — (M1, 2F) OFF
Indoor heating unit expansion valve EV (Y1E) 192 pulse
BS 20RH
Cooling
20RH (Y3S)
No instruction
Heating No instruction
BS 20RT 20RT (Y1S) OFF
Ending condition Max. 5 min.