MITSUBISHI ELECTRIC SKM35ZD-S - Handbuch (Seite 21)

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Self diagnosis function
■
We are constantly trying to do better service to our customers by installing such judges that show abnormality of each function as follows:
Outdoor heat exchanger fluid pipe
sensor error
Outdoor temperature sensor error • Broken outdoor sensor wire, poor connector connection
Description of trouble
Room temperature sensor error
Cause
• Broken heat exchanger sensor (1) wire, poorconnector
connection
• Disconnected sensor
Indoor fan motor error
Heat exchanger sensor (1) error
2 time flash
5 time flash TIMER lamp ON
1 time flash
RUN lamp
2 time flash
1 time flash
TIMER lamp
RUN lamp keeps flashing
• Broken room temperature sensor wire, poor connector connection
• Defective fan motor, poor connector connection
• Broken heat exchanger fluid pipe sensor wire, poor connector
connection
Characteristics of HEAT mode operation
Mechanism and capacity of HEAT mode operation
■ Mechanism
• The unit draws in heat from the cold outside air, transfers it indoors and heats the room. The heating capacity of the heat pump mechanism decreases
when the outside air temperature gets colder.
• The hot air circulation system takes a while before warming up the room temperature.
• If the outside temperature becomes extremely low, it would be better to use an additional source of heating.
Defrosting
If the outside temperature becomes low and humidity is high, the heat exchanger in the outdoor unit may frost over, which prevents efficient heating.
If this happens, the automatic defroster is activated and during defrosting the heating operation stops for 5 to 10 minutes.
• Both indoor and outdoor fans stop and the RUN light (green) blinks slowly (1.5 sec. ON, 0.5 sec. OFF) during defrosting.
• The outdoor unit may give off some steam during defrosting. This is to help the defrosting process and is not a defect.
• The HEAT operation resumes as soon as defrosting has been completed.
2 time flash RUN lamp 2 time flash Rotor lock
• Defective compressor
• Open phase on compressor
• Defective outdoor unit boards
• If heating operation is performed when the outside temperature is high, room temperature may become higher than the set temperature.
Trouble of outdoor unit
Over current
• Compressor locking, open phase on compressor output,
shortcircuit on power transformer, closed control valve
Current cut
2 time flash
3 time flash
1 time flash
Over heat of power transistor
Over heat of compressor
4 time flash
5 time flash
RUN lamp ON
• Broken power transformer, broken compressor wire
• Broken discharge pipe sensor wire, poor connector connection
• Compressor blockage
• Overload operation, overcharge
• Cooling problem
• Gas shortage, defective discharge pipe sensor, closed control
valve
6 time flash Error of signal transmission
• Defective power supply, Broken signal wire, defective in/outdoor
unit boards
Discharge pipe sensor error • Broken discharge pipe sensor wire, poor connector connection
Suction pipe sensor error • Broken suction pipe sensor wire, poor connector connection
• Broken power transistor sensor wire, poor connector connection Power transistor sensor error
4 time flash
5 time flash
6 time flash
6 time flash
7 time flash
Heat exchanger sensor (2) error
• Broken heat exchanger sensor (2) wire, poor connector
connection
• Disconnected sensor
Closed service valve
Heat exchanger sensor (1) error
• Closed service valve
• Disconnected sensor
RWA012A226_En 03.8.27, 6:48 PM 20