Daikin VRV III REYQ8PY1, Service Manual

Page: 135 / 452

Protection Control Si37-701
124 Function
4. Protection Control
4.1 High Pressure Protection Control
This high pressure protection control is used to prevent the activation of protection devices due
to abnormal increase of high pressure and to protect compressors against the transient
increase of high pressure.
[In cooling operation]
★
The following control is performed in the entire system.
Pc_max indicates the maximum value within the system.
Normal Operation
Pc_max
>3.47MPa
Pc_max
>3.55MPa
Pc_max>3.47MPa
Pc_max
<3.24MPa
Pc_max
>3.64MPa
Upper limit compressor step=max (Max. Step)
When occurring 3 times within
30 min., HPS is activated without high
pressure standby, thus outputting the
malfunction code “E3”.
Upper limit
compressor step:
2-step down
After 10 sec.
Current step maintained
Upper limit
compressor step:
1-step up
After 15 sec.
After 10 sec.
High pressure
standby
For multi units:
When STD compressor is in operation
STD compressor standby
When STD compressor stays stopped
52Hz+OFF+OFF (upper limit)
For single unit:
8 to 12HP 52Hz+OFF
14, 16HP 52Hz+52Hz (upper limit)
When high
pressure is limited