Heating Starting Process - Fujitsu Airstage V-II Service Manual

(2) Heating starting process

At the start of heating, the compressor is started by the following process. All compressors start-up
to change the 4 way valve. Capacity control returns to normal control after the end of the starting process.
(target high-pressure control)
< Starting process >
2 compressors outdoor unit (12, 14, 16HP)
Starting process Starting process
Constant speed ON
30rps fixed
Starting process 7 minutes elapsed from start of process
1 minute elapsed from start of process
all outdoor units
Compression ratio of any outdoor unit
Starting process 30 minutes elapsed from start of process
high-pressure of all outdoor units
discharge SH of all operating compressors
*However, when the following condition (A) or (B) are satisfied, starting process is not performed.
< Conditions under which starting process is not performed >
(A) When outside air temperature
(B) When the starting process at heating before stopped at the start of heating
(including thermostat OFF stop) within 30 minutes after heating stopped.
< Operation >
Inverter compressor of all outdoor unit is started at 40rps and normal control immediately begins.
(3) Limits the upper limit speed of the INV compressor according to the present high-pressure value.
High Pressure
3.80MPa
3.30MPa
(Maximum) 3.00MPa
Normal control
70rps fixed
End conditions
or
2.50MPa
or
or
20°C
Maximum speed = 80rps
Maximum speed = 90rps
Maximum speed = 95rps
[ a ]
Maximum speed = 100rps
[ a ] = 1.25
1 compressor outdoor unit (8, 10HP)
Starting process
70rps fixed
and high-pressure of
8
2.63MPa
12
Low pressure value 2.125
02-04
Starting process
70rps fixed
(target high-pressure control)
Normal control