12-21
CONTROL SYSTEM
Revision Y05-01
Service Manual - ALPHA
Deicing procedure
OCT [
o
c]
ON
OFF
ON
OFF
ON
L
ANY
COMP
OFAN
RV
IFAN
DST
(DDT)
0
12
OFF
HEs are forced ON
DOC
ANY
ON
HE
36s
36s
DT
30s
max 12 min.
Note 3
DI (note 1)
DI (note 2)
30s
3 min
3 min
IFAN
OFF
ANY
HE
OFF
ANY
all SH
units
ex
cept WAX
RC or
WAX units
HEs are forced OFF
IFAN is forced to Low Speed
BLINK
ON
OPER
LED
Notes
:
•
At the first COMP activation after SB or OFF, if (OCT < 0
o
c), then DI = 10
min, else DI = 40 min.
•
In the following Deicing cycles, the time interval between two Deicing
cycles activation is between 30 to 80 min (refer to the flow chart).
•
For RC group, HEs are forced OFF. IFAN operation is as in Heat
Mode, Sect 4.0.3.a, i.e. IFAN will be set to OFF when ICT<30
o
c.
For WAX, the IFAN is simply forced OFF.
•
For SH group, HEs are forced ON and IFAN is forced to operate in Low
speed, regardless of the ICT and difference between RAT & SPT.
