Mitsubishi Electric PUZ-ZM200YKA2-ET Service Manual page 49

Check Code Abnormal points and detection method
Pipe temperature
<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 detect.
Note 2: Abnormality P8 is not detected in
drying mode.
Cooling range:
Indoor pipe temperature (TH2 or
TH5)−intake temperature (TH1)
TH: Lower temperature between liquid pipe
temperature and condenser/evaporator
temperature
P8
<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 temperature is not in heating
range within 20 minutes.
Note 3: It takes at least 27 minutes to detect
abnormality.
Note 4: It excludes the period of defrosting
(Detection restarts when defrosting
mode is over)
Heating range:
3°C (condenser/evaporator temperature
(TH5)−intake temperature (TH1)
Abnormal refrigerant circuit
During Cooling, Dry, or Auto Cooling
operation, the following conditions are
regarded as failures when detected for 1
second.
a) The compressor continues to run for 30 or
more seconds.
b) The liquid pipe temperature or the
PL
condenser/evaporator temperature is 75°C
or more.
These detected errors will not be
cancelled until the power source is
reset.
OCH771C
Cause
Slight temperature difference
between indoor room temperature
and pipe <liquid or condenser/
evaporator> temperature
thermistor
• Shortage of refrigerant
• Disconnected holder of
pipe <liquid or condenser/
evaporator> thermistor
• Defective refrigerant circuit
−3°C
Reversed connection of extension
pipe (on plural units connection)
Reversed wiring of indoor/outdoor
unit connecting wire (on plural
units connection)
Defective detection of indoor
room temperature and pipe
<condenser/evaporator>
temperature thermistor
Stop valve is not opened
completely.
Abnormal operation of 4-way valve
Disconnection of or leakage in
refrigerant pipes
Air into refrigerant piping
Abnormal operation (no rotation) of
indoor fan
· Defective fan motor
· Defective indoor control board
Defective refrigerant circuit
(clogging)
49
Judgment and action
Check pipe <liquid or condenser/
evaporator> temperature with room
temperature display on remote controller
and outdoor controller circuit board.
Pipe <liquid or condenser / evaporator>
temperature display is indicated by set-
ting SW2 of outdoor controller circuit
board as follows.
(
Conduct temperature check with outdoor
controller circuit board after connecting
'A-Control Service Tool (PAC-SK52ST)'.
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
evaporator pipe Indoor 1
Indoor 1
1 2 3 4 5 6 1 2 3
ON
OFF
Temperature display of indoor condenser/
Temperature display of indoor liquid pipe
Indoor 2 evaporator pipe Indoor 2
1 2 3 4 5 6 1 2 3
ON
OFF
A-Control Service Tool SW2 setting
Check reversed connection of extension
pipe or reversed wiring of indoor/outdoor
unit connecting wire.
When this error occurs, be sure to
replace the 4-way valve.
Check refrigerant pipes for disconnection
or leakage.
After the recovery of refrigerant, vacuum
dry the whole refrigerant circuit.
Refer to "10-5. HOW TO CHECK THE
PARTS".
Check refrigerant circuit for operation.
To avoid entry of moisture or air into
refrigerant circuit which could cause
abnormal high pressure, purge air in
refrigerant circuit or replace refrigerant.
)
4 5 6
ON
OFF
4 5 6
ON
OFF