Daikin FTXS09HVJU, Service Manual

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SiUS04-904 Control Specification (15/18/24 Class)
Function and Control 53
4.4 Discharge Pipe Temperature Control
Outline The discharge pipe temperature is used as the compressor's internal temperature. If the discharge
pipe temperature rises above a certain level, the operating frequency upper limit is set to keep this
temperature from going up higher.
Detail Divide the Zone
Management within the Zones
4.5 Input Current Control
Outline Detect an input current by the CT during the compressor is running, and set the frequency upper
limit from such input current.
In case of heat pump model, this control is the upper limit control function of the frequency which
takes priority of the lower limit of four way valve activating compensation.
Detail The frequency control is made within the following zones.
When a “stop current” continues for 2.5 seconds after rushing on the stop zone, the compressor
operation stops.
If a “
dropping current” continues for 1.0 second after rushing on the dropping zone, the frequency is
reduced by 2 Hz.
Repeating the above
dropping continues until the current remains in the dropping zone without
change.
In the keep zone, the frequency limit remains.
In the return / reset zone, the frequency limit is cancelled.
Limitation of current dropping and stop value according to the outdoor air temperature
1. In case the operation mode is cooling

The current drops when outdoor air temperature becomes higher than a certain level (model by
Zone Control contents
Stop zone When the temperature reaches the stop zone, stop the compressor and
correct abnormality.
Dropping zone Start the timer, and the frequency is dropping.
Keep zone Keep the upper limit of frequency.
Return / Reset zone Cancel the upper limit of frequency.
Keep zone
(R5470)
A
B
C
D 230
217.4
215.6
213.
8
A°F
B°F
C°F
D°F
Dropping zone
Dropping zone
2 Hz dropping
1.0 second after
rushing in the
dropping zone
Input current
dropping