21
Current protection
When the outdoor unit input current exceeds 15.5A.
These symptoms do not mean any abnor-
mality of the product, but check the follow-
ing points.
• Air filter clogging.
• Amount of gas.
• Short cycle of indoor / outdoor air flow.
Indication
LED 1
(red)
LED 2
(Yellow)
Abnormal point
Detecting method
Check points
Symptom: Oudtoor unit operates (The compressor operates at reduced frequency)
Once
Lighting
Overload protection
When the compressor load exceed the specified value.
Twice
Lighting
High pressure protec-
tion
When indoor pipe temperature exceeds 55
:
during heating.
3 times
Lighting
Defrosting in cooling
When indoor pipe temperature falls to 6
:
or below during cooling.
3 times
Lighting
Discharge temperature
protection
When the discharge temperature exceeds 111
:
.
4 times
Lighting
Low discharge tempera-
ture protection
When the state with low discharge temperature of which 50.4
:
or below
in cool and 48.8
:
or below in heat for 20 minutes.
7 times
Lighting
Defrost thermistor
When a short or open circuit occurs in the defrost thermistor during heat-
ing.
• Check the characteristic of the defrost
temperature thermistor.
Refer to “
F
” on page 25.
• Check the connector. (CN663)
Indication
LED 1
(red)
LED 2
(Yellow)
Abnormal point
Detecting method
Check points
Symptom: Outdoor unit operates
5 times
Lighting
Power factor detection
When the compressor power factor cannot be detected.
• Check the compressor wiring.
6 times
Lighting
Part name
Check method and criterion
12-4. Trouble criterion of main parts
Measure the resistance using a tester.
(Part temperature -10°C ~ 40°C)
Defrost thermistor
Evaporation / Gas pipe
temperature thermistor
Normal
abnormal
5k
Ω
~ 55k
Ω
Opened or short-circuited
Normal
abnormal
100k
Ω
~ 250k
Ω
Opened or short-circuited
Normal
abnormal
2.6k
Ω
~ 3.3k
Ω
Opened or short-circuited
Normal
abnormal
1Each phase 0.39
Ω
~ 0.50
Ω
Opened or short-circuited
Measure the resistance using a tester, after warming up the thermistor by holding by hand.
(Part temperature : 20°C ~40°C)
Discharge temperature
thermistor
Measure the resistance between terminals using a tester.
(Winding temperature : -10°C ~ 40°C)
Compressor
W
U
V
WHT
RED
BLK
Measure the resistance between lead wires using a tester.
(Part temperature : -10°C ~ 40°C)
Outdoor fan motor
Normal
WHT - BLK
BLK - YLW
BLK - RED
Opened or
short-circuited
WHT
YLW
P
ORN
RED
BLK
208.4
Ω
~ 254.8
Ω
42.4
Ω
~ 51.9
Ω
197.7
Ω
~ 241.7
Ω
abnormal
Measure the resistance using a tester. (Part temperature -10°C ~ 40°C)
R. V. coil
Measure the resistance using a tester.(Part temperature -10°C ~ 40°C)
Linear expansion valve
LEV
WHT
RED
YLW BRN
ORN
BLU
Lead wire color
Normal
WHT - RED
RED - ORN
YLW - BRN
BRN - BLU
Abnormal
Opened or short-circuited
37.4
Ω
~ 53.9
Ω
P
Inner protector
OB280-1.qxp 01.4.4 2:40 PM Page 21
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