AYAP7FHR
4 – 2
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
Fig. 1 Temperature properties of indoor thermistors
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
CN2
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.
The room is not heated at all or not heated.
The compressor does not operate.
The control circuit board is normal.
Refrigerant may be leaked.
The running capacitor may be defective.
The outdoor fan motor may be defective.
The outdoor fan motor capacitor may be defective.
The compressor may be defective.
The thermistor may be defective.
Is the voltage
between terminal "N" and
"1" of the terminal board the
power supply voltage ?
NO
Replace the PWB ass'y with a new one.
Push the button of "AUX." on the
indoor unit, and wait 5 sec..
Using a tester, measure voltages at the
terminals on the terminal board.
Select HEAT MODE with remote controller.
And then start operation.
Is the voltage
between terminal "N" and
"2" of the terminal board the
power supply voltage ?
Is the voltage
between terminal "N" and
"3" of the terminal board the
power supply voltage ?
YES
YES
YES
NO
NO
