15
Error Code Abnormal
point and detection method
Cause Countermeasure
P1
Room temperature thermistor (TH1)
1The unit is in 3-minute resume preven-
tion mode if short/open of thermistor is
detected. Abnormal if the unit does not
reset normally after 3 minutes. (The
unit returns to normal operation, if it
has been reset normally.)
2Constantly detected during cooling,
drying, and heating operation.
Short: 90:(194˚F) or more
Open: -40:(-40˚F) or less
1Defective thermistor
characteristics
2Contact failure of connector
(CN20) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of thermistor wiring
4Defective indoor controller
board
1–3Check resistance value of thermistor.
0: (32˚F)• • • • • • • • • • • 15.0k"
10:(50˚F)• • • • • • • • • • • • • 9.6k"
20:(68˚F)• • • • • • • • • • • • • 6.3k"
30:(86˚F)• • • • • • • • • • • • • 4.3k"
40:(104˚F)• • • • • • • • • • • •3.0k"
If you put force on (draw or bend) the lead wire
with measuring resistance value of thermistor
breaking of wire or contact failure can be detected.
2Check contact failure of connector (CN20) on
the indoor controller board. Refer to 10-6.
Turn the power on again and check restart
after inserting connector again.
4Check room temperature display on remote
controller.
Replace indoor controller board if there is abnor-
mal difference with actual room temperature.
Turn the power off, and on again to operate
after check.
P2
Pipe temperature thermistor/Liquid
(TH2)
1The unit is in 3-minute resume
prevention mode if short/open of
thermistor is detected. Abnormal if the
unit does not reset normally after 3 min-
utes. (The unit returns to normal opera-
tion, if it has been reset normally.)
2Constantly detected during cooling,
drying, and heating (except defrosting)
operation.
Short: 90:(194˚F) or more
Open: -40:(-40˚F) or less
1Defective thermistor
characteristics
2Contact failure of connector
(CN21) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of thermistor wiring
4Defective refrigerant circuit is
causing thermistor temperature
of 90:(194˚F) or more or
-40:(-40˚F) or less.
5Defective indoor controller board
1–3Check resistance value of thermistor.
For characteristics, refer to (P1) above.
2Check contact failure of connector (CN21) on
the indoor controller board. Refer to 10-6.
Turn the power on and check restart after
inserting connector again.
4Check pipe <liquid> temperature with remote
controller in test run mode. If pipe <liquid>
temperature is extremely low (in cooling
mode) or high (in heating mode), refrigerant
circuit may have defect.
5Check pipe <liquid> temperature with remote
controller in test run mode. If there is extreme
difference with actual pipe <liquid> temperature,
replace indoor controller board.
Turn the power off, and on again to operate
after check.
P4
Drain sensor (DS)
1Suspensive abnormality, if short/open of
thermistor is detected for 30 seconds
continuously.
Turn off compressor and indoor fan.
2
Short/open is detected for 30 seconds con-
tinuously during suspensive abnormality.
(The unit returns to normal operation, if
it has been reset normally.)
3Detect the following condition.
• During cooling and drying operation
• In case that pipe <liquid> temperature
- room temperature <-10deg
(Except defrosting)
• When pipe <liquid> temperature or
room temperature is short/open tem-
perature.
• During drain pump operation
1Defective thermistor
characteristics
2Contact failure of connector
(CN31) on the indoor controller
board (Insert failure)
3Breaking of wire or contact
failure of drain sensor wiring
4Defective indoor controller board
1–3Check resistance value of thermistor.
0: (32˚F)• • • • • • • • • • • • 6.0k"
10:(50˚F)• • • • • • • • • • • • 3.9k"
20:(68˚F)• • • • • • • • • • • • 2.6k"
30:(86˚F)• • • • • • • • • • • • 1.8k"
40:(104˚F)• • • • • • • • • • 1.3k"
2Check contact failure of connector (CN31) on
the indoor controller board. Refer to 10-6.
Turn the power on again and check restart
after inserting connector again.
4Replace indoor controller board if drain
pump operates with the line of drain sensor
connector CN31-1and 2is short-circuited,
and abnormality reappears.
Turn the power off, and on again to operate
after check.
P5
Malfunction of drain pump (DP)
1Suspensive abnormality, if thermistor
of drain sensor heats itself and
temperature rises slightly. Turn off
compressor and indoor fan.
2Drain pump is abnormal if the condition
above is detected during suspensive
abnormality.
3Constantly detected during drain pump
operation.
1Malfunction of drain pump
2Defective drain
Clogged drain pump
Clogged drain pipe
3Attached drop of water at the
drain sensor
• Drops of drain trickles from
lead wire.
• Clogged filter is causing
wave of drain.
4Defective indoor controller board
1Check if drain pump works.
2Check drain function.
3Check the setting of lead wire of drain sensor
and check clogs of the filter.
4Replace indoor controller board if drain
pump operates with the line of drain sensor
connector CN31-1and 2is short-circuited
and abnormality reappears.
Refer to 10-6.
Turn the power off, and on again to operate
after check.
10-2. SELF-DIAGNOSIS ACTION TABLE Note: Refer to the manual of outdoor unit for the details of display
such as F, U, and other E.
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