Daikin Aurora Series, Service Manual

Page: 69 / 333

SiUS341802E Protection Control
Functions and Control 56
6.2 Low Pressure Protection Control
This low pressure protection control is used to protect compressors against the transient decrease
of low pressure.
Cooling
Heating
Normal Operation
All compressors step: 1
Pe < 0.15 MPa
(21.8 psi)
Pe < 0.25 MPa
(36.3 psi)
Pe > 0.39 MPa
(56.6 psi)
Pe < 0.07 MPa (10.2 psi)
Pe: Low pressure sensor
detection value for master
unit
Master unit: Compressor step: 1
Slave unit: All stop
Abnormal stop
( E4 is displayed)
Low pressure standby
(3 times within 60 minutes)
Low pressure standby
(4 times within 60 minutes)
Normal Operation
9-step down 9-step up
3-step up 21-step down
After 10 seconds After 15 seconds
After 15 seconds After 10 seconds
Pe < 0.07 MPa
(10.2 psi)
Pe < 0.04 MPa
(5.8 psi)
Pe > 0.12 MPa
(17.4 psi)
Pe > 0.09 MPa
(13.1 psi)
Pe < 0.07 MPa
(10.2 psi)
Pe < 0.06 MPa
(8.7 psi)
Compressor step: 1
After 10 seconds
Upper limit compressor step: max (Max. Step)
Pe < 0.03 MPa
(4.35 psi)
Pe: Low pressure sensor
detection value for each
outdoor unit
Current step
maintained
Abnormal stop
( E4 is displayed)
Low pressure standby
(3 times within 60 minutes)
Low pressure standby
(4 times within 60 minutes)