Panasonic CS-ME7CB1P Service Manual page 29

Symbol Diagnosis
F96 IPM (Power transistor
module) or
compressor
overheating
F97 Compressor high
discharge
temperature
F98 Total running current
protection
F99 DC peak detection
When this trouble is detected from the electrical parts radiation fin temperature sensor and OLP output during
operation, operation stops, and it is restarted 3 minutes later. If the trouble occurs on 4 occasions, operation
stops, and the trouble display appears.
<Diagnosis checkpoint>
1. Something may be interfering with the dissipation of the heat outdoors or the outdoor unit fan may be
defective. (The outdoor unit fan is not running.)
2. Defective IPM (outdoor unit control P.C. Board)
3. Gas leaks. Shutting valve is not opened.
This trouble display appears 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 trouble.
2. When operation steps with this trouble display appearing, 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 an open circuit.)
(The protection function may be activated by an overload, and the F97 trouble display 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 trouble display appears.
<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% or 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 outdoors (during cooling
operations): Normally, the capacity is limited by the current so that the outdoor unit don't stop, and the
diagnostic display does not appear.
When "Output current trouble", which occurs when the prescribed current level is exceeded, has occurred on
16 consecutive occasions, operation stops, and the trouble display appears.
<Diagnosis checkpoint>
1. Check whether the compressor is defective (locked up or shorted winding). Check the outdoor unit control
P.C. Board.
CS-ME7CB1P / CS-ME10CB1P / CS-ME12CB1P / CS-ME14CB1P / CS-ME10CD3P / CS-ME14CD3P
Diagnosis method
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