Daikin FTXS09HVJU, Service Manual

Page: 52 / 274

Control Specification (09/12 Class) SiUS04-904
42 Function and Control
3.7 Heating Peak-cut Control
Outline During heating operation, the signals being sent from the indoor unit allow the operating frequency
limitation and prevent abnormal high pressure. The signal from the indoor unit must be divided as
follows:
Detail Conditions for Start Controlling
Judge the controlling start with the indoor heat exchanger temperature after 2 seconds from
operation start.
Control in Each Zone
The heat exchanger’s intermediate indoor unit temperature controls the following:
3.8 Fan Control
Outline Fan control is carried out according to the following conditions.
1. Fan control when defrosting
2. Fan OFF delay when stopped
3. ON/OFF control when cooling operation
4. Tap control when
dropping function is working
5. Fan control when forced operation
6. Fan control in low noise mode
7. Fan control during heating operation
8. Fan control in the quiet mode
9. Fan control in the POWERFUL mode
10. Fan control for pressure difference upkeep
Detail
Fan OFF Control when Stopped

Fan OFF delay for 60 seconds must be made when the compressor is stopped.
3.9 Liquid Compression Protection Function 2
Outline
In order to ensure the dependability of the compressor, the compressor must be stopped according
to the conditions of the temperature of the outdoor air and outdoor heat exchanger.
Detail

Operation stops depending on the outdoor air temperature
Compressor operation turns OFF under the conditions that the system is in cooling operation and
outdoor air temperature is below 10.4°F(–12°C).

Operation can be extended to 0°F (17-18°C) (RXS-DAVJU only) with the addition of a wind
baffle (KPW937A4).
Dropping zone