Daikin VRV EMERION RXYQ-AATJA, Service Manual

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SiUS342303E Startup Control
Part 4 Functions and Control 102
4. Startup Control
This control is used to equalize the pressure in the suction and discharge sides of the compressor
prior to the startup of the compressor, thus reducing startup loads. Furthermore, the inverter is
turned ON to charge the capacitor.
To avoid stresses to the compressor due to liquid refrigerant return or else after the startup, the
following control is made and the position of the four way valve is also determined. Start both the
master and the sub units simultaneously to position the four way valve.
DSH: Discharge pipe superheating degree
Pc: High pressure sensor detection value
Pe: Low pressure sensor detection value
Ta: Outdoor air temperature
4.1 Startup Control in Cooling
4.2 Startup Control in Heating
0 rps
0 pulse
3,000 pulse (fully open)
EV indoor opening
Tcmax > 48°C (118.4°F)
OR
Ta < 20°C: OFF
(68°F)
Ta ≥ 20°C: Step 4
(68°F)
Rotation speed step up
5 sec. interval
+1 step/15 sec. (Pc > 2.16 MPa (313 psi)
–1 step/15 sec. (Pc < 1.77 MPa) (257 psi)
Compressor motor
(M1C) (M2C)
Electronic expansion
valve (Y1E) (Y6E)
Fan motor
(M1F + M2F)
Pc – Pe > 0.17 MPa (24.7 psi)
A
B
C
D
E
Step 4
0 rps
+ F /10 sec.
A
B
C
D
E
0 pulse
Maximum step
PI control
Compressor motor
(M1C) (M2C)
Electronic expansion
valve (Y1E) (Y6E)
Fan motor
(M1F + M2F)
Rotation speed step up
5 sec. interval
Initial
opening
Pcmax > 2.45 MPa (355 psi) Pc – Pe > 0.17 MPa (24.7 psi)
Step 1
A
Frequency
(rps)
RXYQ72AA
RXYQ96/120AA RXYQ144/168AA RXYQ192/216/240AA
M1C M2C M1C M2C M1C M2C
A 15 26 26 26 15 15 15
B 23 37 37 37 23 23 23
C 28 45 45 45 28 28 28
D 37.3 60 60 60 37.3 37.3 37.3
E 51.4 82 82 82 51.4 51.4 51.4
F 6.2 5 5 3.8 3.8 6.8 6.8