Fan Control; Cooling Operation; Heating Operation - Fujitsu Airstage V series Service Manual

(2) In order to enhance reliability and endurance of system, it is monitoring accumulating time of
each compressor operating in the same refrigerant system.
And when accumulating time of operating is over predetermined time, the compressor is stopped and
the rest of stopped compressor is started.
Thus, operating time of each compressor is averaged(Rotation operation).

4-3 FAN CONTROL

4-3-1 Cooling operation

After starting the outdoor unit, the fan speed of outdoor unit is decided by outdoor air temperature.
NORMAL MODE
FAN 1
Step 1 Hi
Step 2 Hi
Step 3 Lo
Step 4 Lo
Step 5 stop
When turning on DipSW2-1(Silent operation mode),
switching conditions of Normal mode and Silent mode are as follows.
NORMAL MODE
Switching conditions of step
High pressure saturation temperature < Target high pressure temperature,
and inverter heatsink temperature
(The thermistor is built- in the inverter PCB.)
(High pressure saturation temperature - Target high pressure temperature) > About 10
Or inverter heatsink temperature
Step 1

4-3-2 Heating Operation

Heating operation is performed at Hi all the time.
FAN SPEED
SILENT MODE
FAN 2 FAN 1 FAN 2
Hi Lo Lo
Lo Lo Lo
Lo Lo Lo
Lo
stop stop
stop stop stop
Tout < 29 & HP < 2.96MPa
Tout > 33 or HP > 3.57MPa
75
80
Step 2 Step 3
04-05
OUTDOOR AIR
TEMPERATURE
(Tout)
Tout > 25
15 < Tout 25
5 < Tout 15
Tout 5
Tout : Outdoor air temperature
HP : High pressure
SILENT MODE
(It depends on the outdoor air temperature)
Step 4 Step 5