Daikin RXQ12AHR Service Manual page 155

SiAF341904E
 m2-90: Indoor unit without power U4 error generation. In case an indoor unit needs
Part 5 Field Settings and Test Operation
 2: Quick. Undershoot during cooling operation is allowed compared to the requested
refrigerant temperature, in order to achieve the required room temperature very fast.
The overshoot is allowed from the start up moment. In case of cooling operation the
evaporating temperature is allowed to go down to 6°C on temporary base depending
on the situation. When the request from the indoor units becomes more moderate, the
system will eventually go to the steady state condition which is defined by the
operation method above.
 3: Powerful. Undershoot during cooling operation is allowed compared to the
requested refrigerant temperature, in order to achieve the required room temperature
very fast. The overshoot is allowed from the start up moment. In case of cooling
operation the evaporating temperature is allowed to go down to 3°C on temporary
base depending on the situation. This setting is used in conjunction with setting 2-8.
 The graph below shows the different patterns of target Te according to setting 2-81
"cooling comfort setting"
Refrigerant temperature
Target
Te
Te 6°C
Te 3°C
maintenance or repair on the electric side, it is possible to keep the rest of the VRV DX
indoor units operating without power supply to some indoor unit(s).
 Default value: 0. Not active.
 Field setting 1: Possible to operate system when some indoor units are temporary
without power supply. The following conditions must be fulfilled:
 Maximum equivalent piping length of the farthest indoor less than 120 m.
 Index indoor units power simultaneously less than 30% of the nominal outdoor.
 Total capacity is less than 30% of the nominal one of the outdoor unit.
 Operation time is limited to 24 hours period.
 It is recommended to shut down connected indoor units at the same floor.
 Not possible to use service mode operation (e.g. recovery mode).
 Backup operation has priority over this special feature.
 Not possible to use when the indoor unit electronic expansion valve is defective.
 Not possible to use with systems that include BP units.
 It is necessary to wait for 10 min. before shutting down the connected indoor units
after indoor units operation is stopped.
Field Settings for Outdoor Unit
Powerful mode
Quick mode
Mild mode
time
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