Error
Abnormal point and detection method
Code
temperature of over 70˚ C [158˚ F] is detected again within
10 minutes after six-minute resume prevention mode.
P8
Pipe temperature
(1503)
<Cooling mode>
Detected as abnormal when the pipe temperature is not in the
cooling range 3 minutes after compressor start and 6 minutes
after the liquid or condenser/evaporator pipe is out of cooling
range.
NOTE
1) It takes at least 9 minutes. to de-
tect.
2) Abnormality P8 is not detected in
drying mode.
Cooling range: -3˚ C (-5.4˚ F) ] (TH-TH1)
TH: Lower temperature between: liquid pipe temperature (TH2)
and condenser/evaporator temperature (TH5)
TH1: Intake temperature
<Heating mode>
When 10 seconds have passed after the compressor starts
operation and the hot adjustment mode has finished, the unit is
detected as abnormal when condenser/evaporator pipe tempera-
ture is not in heating range within 20 minutes.
Specifications are subject to change without notice.
PAA-A18, 24, 30, 36, 42AA1/BA1/CA1 and all-
5.
6.
7.
(Heating mode)
1.
2.
3.
4.
5.
6.
7.
8.
1.
2.
3.
4.
5.
47
Cause
Defective outdoor fan con-
trol
Overcharge of refrigerant
Defective refrigerant circuit
(clogs)
Clogged filter (reduced air-
flow)
Short cycle of air path
Over-load (high tempera-
ture) operation beyond the
tolerance range
Defective furnace fan mo-
tor
• Fan motor is defective.
• Indoor controller board is
defective.
Defective outdoor fan con-
trol
Overcharge of refrigerant
Defective refrigerant circuit
(clogs)
Bypass circuit of outdoor
unit is defective
Slight temperature differ-
1~4. Check pipe <liquid or condenser / evapora-
ence between indoor room
tor> temperature with return air temperature dis-
temperature and pipe <liq-
play on remote controller and outdoor controller
uid or condenser / evapora-
circuit board.
tor> temperature thermistor
• Shortage of refrigerant
Conduct temperature check
• Disconnected holder of
with outdoor controller circuit
pipe < liquid or condenser /
board after connecting
evaporator > thermistor
'A-Control Service Tool
• Defective refrigerant cir-
(PAC-SK52ST)'.
cuit
Converse connection of ex-
2~3. Check converse connection of extension
tension pipe (on plural units
pipe or converse wiring of indoor/outdoor unit
connection)
connecting wire.
Converse wiring of indoor/
outdoor unit connecting
wire (on plural units con-
nection)
Defective detection of in-
door return air temperature
and pipe < condenser /
evaporator > temperature
thermistor
Stop valve is not opened
completely
Countermeasure
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