Fujitsu FO20R Series Installation Instructions Manual page 42

8.0 ACTIVE SYSTEM PROTECTION FEATURES
8.13 Sensor Failure Default Operation
If the controls sense an externally connected sensor
has failed, the system will enter a fail safe operating
mode and will continue to condition the space until
the sensor can be replaced. A fault code will be
8.14 Exiting Active Protection Lock-Out Mode
Exiting an Active Protection Lock-Out mode can
be accomplished by disconnecting electrical power
to both the indoor and outdoor units for 1 minute
and then restoring power. Keep in mind there
was a reason for the lock-out, so the fault code
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displayed on the Digital Control Center and Variable
Speed Outdoor Control identifying which sensor has
failed. See the table below for the default operation
for a sensor failure.
on the Variable Speed Outdoor Control (VSODC)
or Digital Control Center should be read to assist
with diagnosing the root cause of the lock-out and
corrective action should be taken to prevent the
system from repeating the lock-out.