Hitachi RAS-10HRNM, Service Manual, Page: 136 / 482

5.4 Standard operation sequence
5.4.1 Standard operation sequence for IVX Series
Cooling operation
Temp.
on the top
of comp.
Power to
O.U.: ON
Power to CH : ON
Power to CH : OFF
I.U.: Indoor unit
O.U.: Outdoor unit
Power to
I.U.: ON
Power to PCB in
I.U.: ON
Start of transmission between
I.U. and O.U.
Start of transmission between
I.U. and remote control switch
Auto-louver 0 reset
Power to YH2 in
I.U.: OFF
FS
MD : ON
≤ 55 ºC
OFF
(Higher than
activation level)
ON
(Lower than activation level)
(for unit with drain pump)
Setting at
COOL
COOL indication
Set temp. indicated
Pressing
TEMP.
switch
Switch: increasing set temp.
Switch: decreasing set temp.
Pressing
RUN/STOP
switch
Run LED:ON, RUN is indicated
Indication of unit
stoppage cause (d1-22)
After
power
supply
Temp.
on the top of
comp.
Temp.
on the top of
comp.
Temp.
on the top of
comp.
< 4 hours
(* < 2 hours)
≥ 4 hours
(* ≥ 2 hours)
< 50 ºC
(* < 30 ºC)
≥ 50 ºC
(* ≥ 30 ºC)
< 40 ºC
(* < 30 ºC)
≥ 40 ºC
(* ≥ 30 ºC)
< Ta+20 ºC
≥ Ta+20 ºC
I.U. Air
intake temp.
COOLING
operation
to 1
Higher than set
temp. +2 ºC
Lower than
set temp.
< -5 ºC
≥ -5 ºC
Power to
Y52C : ON
1
sec.
Outdoor
temp.
No
Yes
Outdoor fan
MOF operation
* Test Run:
Hot start protection is activated
after 2 hours or 30ºC.
* Standard operation:
Hot start protection is activated
after 4 hours or 40ºC.
Power to PCB in
O.U.: ON
Power to YH2 in
I.U.: ON
Pressing
FAN switch
Air
over switch
HIGH indication
MEDIUM indication
LOW indication
Power to YH2 for
20 sec.
Operation at set indoor fan speed
MD : ON
for unit with drain pump
Power to EHW:ON
for unit with EHW
Power to
CMC : ON
Power
Power to YH2 in
I.U.:OFF
MD : ON
Power to
EHW:ON
(for unit with drain pump)
(for unit with EHW)
Only RAS-8~12HRNM
A
A
≥ 60 ºC
Only for I.U. with
auto-louver
Continues in the next page.
5 Control System
128
SMGB0060 rev. 1- 12/2010