Daikin VRV - WII, Service Manual

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Startup Control SiUS30-604
62 Function
4. Startup Control
This startup control is used to provide the following control to reduce the compressor load resulting
from liquid return or else during compressor startup, and also determine the position of four way
valves.
4.1 Cooling Start-up Control
Both master and slave units operate same time for changing 4 way valve position
→
Normal
operation after completion.
Parts name Symbol
Electrical
symbol
Pressure equalization
control before start-up
Starting control
Compressor — (M1C) 0 Hz
52Hz
+2 steps/20 sec.
(until Pc-Pe > 71.05 psi)
Inverter cooling fan — (M1, 2F) OFF
Inverter cooling fan
control
4 way valve (Main) 20S1 (Y5S) Holding OFF
4 way valve (for heat exchanger) 20S2 (Y7S) Holding OFF
Main heat exchanger electronic exp. valve EV1 (Y1E) 0 pulse 2000 pulse
Sub-cooling electronic exp. valve EV3 (Y3E) 0 pulse 0 pulse
Hot gas bypass solenoid valve SVP (Y1S) OFF ON
Water heat exch. oil return solenoid valve SVE (Y2S) OFF OFF
Receiver gas charging solenoid valve SVL (Y3S) OFF OFF
Receiver gas discharge solenoid valve SVG (Y4S) OFF OFF
Non-operation unit liquid pipe stop
solenoid valve
SVSL (Y6S) ON ON
Indoor unit fan — (M1, 2F) Indoor unit control Indoor unit control
Indoor unit expansion valve EV (Y1E) 0 pulse
0 pluse Initial
opening
BS 20RH
Cooling
20RH (Y3S) OFF OFF
Heating
BS 20RT 20RT (Y1S) OFF OFF
Ending condition 1 minute Max. 5 minutes
Thermostat ON