Startup Control In Heating - Daikin VRV RXYQ72-384XAYCA Service Manual

SiUS342004EB
4.2

Startup Control in Heating

Compressor
0 Hz
(M1C)
Electronic expansion
0 pulse
valve (main)
(Y1E)
Fan motor Step 4
(M1F + M2F)
Pc – Pe > 0.17 MPa (24.7 psi)
DSH : Discharge pipe superheating degree
Pc : High pressure sensor detection value
Pe : Low pressure sensor detection value
Part 4 Functions and Control
Frequency step up
+10 rps/10 sec.
5 sec. interval
E
D
C
B
A
PI control
Initial
opening
Step 8
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 > 12°C (21.6°F)
Startup Control
RXYQ72-120XA RXYQ144/168XA
RXYQ72-120XB RXYQ144/168XB
19 16.4
16.4
24
29 18
38 24
57 36
86