Sharp AE-X12PSR, Service Manual, Page: 24 / 73

SHARP(CHINA)INVESTMENT CO.,LTD
ƽ
when the unit enter drop frequency prevention opreates, if I
drop
I
outdoor
I
normal
, the controller limit the operation frequency rise until I
outdoor
˘
I
normal
.
ƽ
When the outdoor current I
max
, the compressor stops and outdoor
motor stops after 15 seconds
1.12. Compressor drive prevention
During the compressor start up or operation, if the signal of the
compressor can’t be checked or check the load is exceptonal or driver fail
then shut down the outdoor unit and displays the fail code.
1.13. Indoor unit evaporator freeze prevention
When the indoor evaporator temperature IPT4
ć
and keeps 1 minutes,
the uint enter the evaporator freeze prevention. If the indoor evaporate
temperature IPT-1
ć
and remains 5 minutes during cooling or dry
operation, the compressor stops in order to prevent the freezer and
displays code P5.
When the indoor unit evaporator temperature IPT6
ć
, the compressor
restarts and resumes normal operation.
1.14. Outdoor unit overheat prevention
During cooling operation, if the temperature of the outdoor unit
heat-exchanger OPT
exceeds the limit frequency rise temperature TOP2,
the contoller limit the operation frequency rise unti the OPT ˘ TOP2.
If if the temperature of the outdoor unit hea-texchanger OPT reach or
exceeds stops unit temperature TOP4, the compressor stop
operating,until OPTTOP1(prevention cancel temperature), the unit
restart and opreates at normal.
1.15. Indoor unit overheat prevention control
During heating operation, if the temperature of the indoor unit
heat-exchanger IPT exceeds the limit frequency rise temperature TIP2,
the contoller limits the operation frequency rise unti the IPT
˘
TIP2.
If the temperature of the outdoor unit heat-exchanger IPT reaches or
exceeds stops unit temperature TIP4, the compressor stops operating
and diplayes code P7,until IPTTIP1(prevention cancel temperature), the
unit restart and opreates at normal.
1.16. IPM pretector
If the IPM checked the temperature itself or current is higher than prevent
temperature or current, the contrller shuts down the outdoor unit and
displays code P0, when the IPM temperature or current drops to lower
than prevention temperature, the outdoor unit restarts and operates at
normal.
1.17. Startup control
When the air conditioner starts in the cooling or heating mode, if the room
temperature is 3.5°C higher than the set temperature, the unit operates
with the operating frequency at maximum. Then, when the set
temperature is reached, the unit operates at the operating frequency
determined by fuzzy logic calculation, then enters the normal control
mode after a while.
1.18. Cold air prevention control
When the air conditioner starts up in heating mode, the indoor unit fanwill
not operate until the temperature of the indoor unit heat excharge reaches
about 33°C in order to prevent cold air from blowing into the room.
Also, the indoor unit fan operates at low speed until the temperature ofthe
indoor unit heat exchanger reaches about 37°C so that people inthe room
will not feel chilly air flow.
1.19. Auto restart
When power failure occurs, after power is recovered, the unit will
automatically restart in the same setting which auto restart function
were active before the power failure, except for timer settings.
If a power failure ocurse while the timer is set, the timer setting will
be cancelled and willl not be retrived even after the power is
restored.
1.20. Defrosting
Defrosting is controlled by the microprocessor.
1.20.1. conditions of defrosting
The defrost operation starts when the one of the following conditions
is satisfied, the unit will come into defrosting. When the defrost
operation starts, if the indoor excharge temperature less than 34
ć ,
the indoor unit fan stops.
a. utdoor heat exchanger Temperature (OPT) is continuously up
to or less than 3 ć while the unit runs for more than 40 minutes,
and OPT is keep under -6 ć for more than 3 minutes.
b. Outdoor heat exchanger Temperature (OPT) is continuously uo
to or less than 3 ć meanwhile the unit runs for more than 80
minutes, and OPT is keep under -4
ć
for more than 3 minutes.
c. Outdoor heat exchanger Temperature (OPT) is continuously up
to or less than 3
ć
while the unit runs for more than 120
minutes, and OPT is keep below -2 ć for more than 3 minutes.
d. Once in the heating mode, if the outdoor heat excharge
temperature(OPT) keep lower than 0 ć and outdoor tempera-
ture higher than 3
ć
, also the compressor operates for more
than 20 minutes and the outdoor heat exchanger Temperature
(OPT) reaches -6
ć
or less and keeps 3 minutes, enter the first
defrost.
The defrost operation stops when the outdoor unit heat-exchanger
temperature rises to about 15°C or higher or the defrosting time
exceeds 10 minutes.
1.20.2. Compressor operation frequecy
Before the air conditioner come into defrosting, compressor running
frequen- cy drop down to a lower frequency firstly, then the compre-
ssor shuts down.
In defrosting, the max. frequency of compressor is F9, in this period
all protection functions are avaliable.
1.20.3 The part operation order.
34
ć
low fan speed
set fan speed
temperature
drop
22 ć
stop
soft
28 ć
33 ć
37
ć
25 ć
temperature
rise
10S 50S 15S İ 10minutes 15S
ON
OFF
OFF
ON
OFF
ON
outdoor fan motor
4-way valve
compressor
2-1 9