Startup Control; Startup Control In Cooling - Daikin Aurora Series Service Manual

Startup Control

4. Startup Control

This control is used to equalize the pressure in the front and back 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 oil 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 slave units simultaneously to
position the four way valve.
4.1

Startup Control in Cooling

Inverter compressor
(M1C)
0 pulse
Electronic expansion
valve (main)
(Y1E)
Step 15
Inverter fan
(M1F + M2F)
DSH: Discharge pipe superheated degree
Pc : High pressure sensor detection value
Pe : Low pressure sensor detection value
Ta : Outdoor air temperature
Refer to page 53 for Step X.
45
Frequency step up
5 sec. interval
E
D
C
B
A
0 Hz
3,000 pulse (fully open)
Ta < 20˚C: OFF
(68˚F)
Ta ≥ 20˚C: StepX/2
+3step/15 sec. (Pc > 2.16 MPa (313 psi))
–3step/15 sec. (Pc < 1.77 MPa (257 psi))
(68˚F)
Pc – Pe > 0.17 MPa (24.7 psi)
Frequency
(rps)
A
B
C
D
E
Pc – Pe > 0.42 MPa (60.9 psi)
Pc – Pe > 0.32 MPa (46.4 psi)
&
OR
20 rps or more
DSH > 10˚C (18˚F)
SiUS341802E
RXLQ72TA RXLQ96/120TA
RXYQ72-120TA RXYQ144/168TA
19 16.4
24 16.4
29 18
38 24
57 36
Functions and Control