Outdoor Fan Control; Liquid Compression Protection Function - Daikin FFQ09Q2VJUFFQ12Q2VJUFFQ15Q2VJUFFQ18Q2VJURX09QMVJURX12QMVJURX15QMVJURX18QMVJU Service Manual

SiUS091628EA
2.8

Outdoor Fan Control

1. Fan ON control to cool down the electrical box
The outdoor fan is turned ON when the electrical box temperature is high while the compressor is
OFF.
2. Fan OFF control during defrosting
The outdoor fan is turned OFF during defrosting.
3. Fan OFF delay when stopped
The outdoor fan is turned OFF 60 ~ 70 seconds after the compressor stops.
4. Fan speed control for pressure difference upkeep
The rotation speed of the outdoor fan is controlled for keeping the pressure difference during
cooling operation with low outdoor temperature.
5. Fan speed control during forced cooling operation
The outdoor fan is controlled as well as normal operation during forced cooling operation.
6. Fan ON/OFF control when operation (cooling, heating, dry) starts/stops
The outdoor fan is turned ON when the operation starts. The outdoor fan is turned OFF when the
operation stops.
2.9

Liquid Compression Protection Function

Outline In order to increase the dependability of the compressor, the compressor is stopped according to
the outdoor temperature.
Details Operation stops depending on the outdoor temperature
Compressor turns off under the conditions that the system is in cooling operation and outdoor
temperature is below 0°C (32°F).
Functions and Control
When the pressure difference is low, the rotation speed of the outdoor fan is reduced.
When the pressure difference is high, the rotation speed of the outdoor fan is controlled as well
as normal operation.
Control Specification
38