Panasonic CS-ME7EB1E Service Manual page 30

CS-ME7EB1E / CS-ME10EB1E / CS-ME12EB1E / CS-ME14EB1E
Symbol Diagnosis
F97 Compressor high
discharge temperature
F98 Total running current
protection
F99 DC peak detection
This error occurs and operation stops when this happens on 6 occasions (it is cleared when the operation is
normal for 20 minutes).
<Diagnosis checkpoint>
1. Check the refrigerating cycle: Gas may be leaking (The amount of refrigerant is low). The stopping of the
outdoor unit from time to time is a symptom of this error.
2. When operation steps with this error occurs, check the compressor temperature sensor. (Check for changes
in its characteristics and check its resistance.)
3. Something may be interfering with the dissipation of the heat outdoors or the outdoor unit fan may be
defective. (The fan will not run because of open-circuiting.)
(The protection may be activated by an overload, and the F97 error will remain stored in the memory.)
When the total current exceeds the setting (17A to 20A), frequency control is started, and if it then exceeds the
setting, operation stops, and the error occurs.
<Diagnosis checkpoint>
1. Check the AC voltage at the outdoor unit terminal board during operation: The voltage drop must be within
5% of the voltage when operation has stopped (±110% of rated voltage even during operation). If the voltage
drop exceeds 5% of if the voltage changes suddenly, inspect whether the power supply cord and
indoor/outdoor unit connection cables are too long or too small in diameter, etc.
2. Check whether something is interfering with the dissipation of the heat exchanger outdoors (during cooling
operation): Normally, the capacity is limited by the current so that outdoor unit doesn't stop, and the
diagnostic display does not appear.
When "Output current error", which occurs when the prescribed current level is exceeded, has occurred on 16
consecutive occasions, operation stops, and the error occurs.
<Diagnosis checkpoint>
1. Check whether the compressor is defective (locked up or shorted winding). Check the outdoor unit control
P.C. Board.
Diagnosis method
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