Fujitsu Airstage J-II, Service Manual

Page: 31 / 209

(2) Target low-pressure and high-pressure control
In order to make the evaporation pressure of the indoor unit at the proper pressure on a variety of operations,
capacity of the compressor will be controlled by low-pressure sensor of the outdoor unit.
In order to make the condensation pressure of the indoor unit at the proper pressure on a variety of operations,
capacity of the compressor will be controlled by high-pressure sensor of the outdoor unit.
Target low-pressure and high pressure temperature depends on system capacity, capacity of compressor operation,
pipe length, and capacity shift switch settings.
<Cooling>
<Heating>
02-03
2-2-3 Speed Range of Start, Stop, And Operation
On stop mode : 0 rps
On operating mode : 20 - 100 rps
(1) Cooling starting process
For cooling operation only, the upper limit speed at starting is made 50rps and is raised in
+10rps increments every 60 seconds.
S
pe
ed
Time
0
50rps
60sec
Target speed
60
sec
60sec
60rps
70rps
80rps
60sec
120
sec
180
sec
240
sec
90rps
10rps
10rps
The compressor operates at the upper limit speed if the target speed is higher than the upper limit speed.
The compressor operates at the target speed if the target speed is lower than the upper limit speed.
60sec
10rps