DOWNLOAD Sharp AU-A24 (serv.man12) Service Manual ↓ Size: 4.91 MB | Pages: 36 in PDF or view online for FREE

17

YES

NO

NO

YES

The machine does not function
with remote controller 

Push button "OI" on the wireless 
remote controller.

Is transmitting

indicator of the remote 

controller active ?

Is indicator lamp of

indoor unit proper ?

Replace the 
PWB  with a 
new one.

Does beep sound

from the indoor unit ?

Using a tester,
measure the voltage
between terminals
of resistor R26
on the PWB ass'y.

Push the button "OI".

Are batteries of the

wireless remote controller 

proper ?

Replace the batteries 
with new ones.

Replace the wireless
remote controller.

When the signal is

received, does the voltage

change ?

Replace the PWB with a new 
one.

PWB is normal.
Inspect the outdoor unit.

NO

YES

NO

YES

Replace the photo 
detector unit with a new 
one.

NO

YES

18

The room is not cooled at all
or not cooled.
The compressor does not operate.

Measure resistances of TH1 and TH2.

Push the button "AUX." on 
the  indoor unit, for more than 5 sec.

Is the voltage

between terminal "N" and

"1" of the terminal board the

power supply voltage ?

Are the resistances

conformed Fig. 1 ?

Replace the thermistor ass'y 
with a new one.

NO

YES

YES

NO

Replace the PWB ass'y with a new one.

Using a tester, measure voltage at
the terminals on the terminal board.

100

80

60

40

20

0

-10

0

10

20

30

40

Resistance

Thermistor

Room temperature

Heat exchange

Color

Yellow

Orange

To measure the resistance, first remove 
the connector as shown at right.

Room temperature 

thermistor TH1

Tester

Connector

No. 3 to 4

No. 1 to 2

K

Heat exchange thermistor 
TH2 (orange)
25

°C resistance 15 K 

Room temperature 
thermistor TH1 (yellow)
25

°C resistance 10 K

Heat exchange 

thermistor TH2

Tester

4

1

CN4

The control circuit is normal.
   The compressor may be defective.
   The running capacitor may be 
   defective.
   Refrigerant may be leaked.
   The outdoor fan motor may be 
   defective.
   The outdoor fan motor capacitor 
   may be defective.

19

The room is not cooled at all
or not cooled.
The compressor does not operate.

Measure resistances of TH1 and TH2.

The control circuit is normal.
   The compressor may be defective.
   The running capacitor may be 
   defective.
   Refrigerant may be leaked.
   The outdoor fan motor may be 
   defective.
   The outdoor fan motor capacitor 
   may be defective.

Push the button " AUX." on  
the indoor unit, for more than 5 sec.

Is the voltage

between terminal of black 

lead wire on the relay in the outdoor unit 

and terminal "N"  on the terminal board the 

power suuply voltage ? 

Are the resistances

conformed Fig. 1 ?

Replace the thermistor 
ass'y with a new one.

NO

YES

YES

NO

Replace the PWB ass'y with a new one.

Using a tester, measure voltage at
the terminals on the terminal board.

Replace the relay in the outdoor unit with 
a new one.

Is the voltage

between terminal " N " and

" 2 " in the outdoor unit 

the power supply 

voltage ?

YES

NO

20

1

2

Capillary tube

3

Outdoor unit

Condenser

Evaporator

Indoor unit

Compressor

Flare coupling

Flare coupling

4

3-way
valve

2-way

valve

Accumulator

O.D.

I.D.

L

Capillary tube

ø 3.5

ø 2.2

900

O.D.

I.D.

L

Capillary tube 

ø 3.2

ø 2.0

700

AH-AP18CS

AH-AP24CS

Indoor side

Outdoor side

Temperature (˚C)

Temperature (˚C)

Relative humididity (%)

Relative humididity (%)

29

39

46

14

Cooling

AH-AP18CS

AH-AP24CS

Cooling

Cooling

Model

NO. Condition

SASO Cooling Condition (at 220V refrigerant pipes length 7.5m)

1

2

3

4

Service port pressure

104˚C

103˚C

55˚C

52˚C

14˚C

23˚C

6˚C

6˚C

0.56MPa

0.59MPa