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(3)
Miscellaneous
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When encountering problems other than the ones listed above, the system, except for the fan (unless
problems are found with the fan-in which case the fan will also stop), will stop.
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When problems are found in only one of the two units of a 2-refrigerant circuit, only the unit with problems
will run an emergency operation or stop its operation, while the other unit will keep running its normal
operation.
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Emergency operation is intended only as a first aid until the unit is serviced. Have the unit serviced with-
out delay to restore a normal operation.
[5] Three-minute restart-suspension mode
The unit will be in a three-minute restart-suspension mode (same operation as Thermo OFF) in any of the fol-
lowing situations.
· When the demand for outdoor unit changes from Thermo ON to Thermo OFF.
· When operation mode changes from normal to emergency mode.
· When anti-freeze mode is completed.
✻
Outdoor unit also has a three-minute restart-suspension mode, and it works independently of the
indoor unit.
[6] Anti-Freeze Control
(1) Starting Conditions
This operation will start when all of the following conditions are met:
· Thermo ON status has been detected for 16 minutes.
· TH22 (liquid pipe temp. Thermistor) < 1˚C has been detected for 20 minutes.
(2) Control Operation
The unit will be in the same condition as Thermo OFF condition for six minutes. When the following conditions
are met, the unit will be in a 20-second restart-suspension mode.
(3) Stopping Conditions
When either of the following conditions is met:
· HT22 10˚C
· Six minutes have elapsed since the beginning of this operation.
[7] Operation during Electrical Power Failure
After the controller in this air conditioning unit receives signals indicating power failure or an instantaneous
drop in voltage, unless the unit receives a command not to restart, it will resume its operation after power
supply is restored.
Depending on the duration of power outage, the following operations will be run.
Note 1: When indoor unit is in the maintenance mode (SW8 local mode), it will not resume operation even
after the power has been restored.
Note 2: After the unit resumes its operation, MA remote controller will display 'HO' for fifteen seconds, during
which time the remote controller will not respond. To turn off the unit during this time, turn off the
power with an electric leak breaker.
Duration of Power Outage
Unit Operation
Shorter than 6msec
Both indoor and outdoor units will stay on.
Longer than 6msec and
Shorter than 50msec
(Note1, Note2)
It is recognized by the unit as aninstantaneous power outage
Indoor Unit: The fan stays on.
Outdoor Unit: Compressor stops, then resumes its operation 3 minutes later.
✻
Note on the outdoor unit: When the power supply is cut off for longer
than 6 msec, compressor will stop.
Longer than 50msec
(Note1, Note2)
It is recognized by the unit as power outage.
Air-conditioning unit will stop (incl. fan and compressor).
It will resume operation after the power has been restored.
