Mitsubishi Electric MS-18NN Series Service Manual page 22

9. EMERGENCY-TEST OPERATION
When the remote controller is missing, has failed or the batteries run down, press the Emergency operation switch button
on the front of the indoor unit. The unit will start and the Operation lamp will light.
The first 30 minutes of operation will be the test run operation. This operation is for servicing. The indoor fan runs at high
speed and the system is in continuous operation. The thermostat is ON and the timer is reset to normal.
After 30 minutes of test run operation the system shifts to emergency run operation with a set temperature of 24°C in
cooling.
The fan shifts to MED speed.
This operation continues until the Emergency operation switch is pressed or a button on the remote controller is pressed,
then normal operation will start.
The coil frost prevention circuit operates in this mode.
In the test run or emergency operation, auto vane operates in AUTO mode with the set temperature 24°C.
NOTE : Do not press the Emergency operation switch during normal operation.
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