Low Pressure Protection Control - Daikin RTSQ20PY1 Service Manual

SiBE31-801_C
7.2

Low Pressure Protection Control

This function is used to conduct low-pressure protection control on outdoor units, in order to
protect compressors from transient drops in low pressure.
[In cooling operation]
★
Pe < 0.34MPa
All STD compressors stop
Pe < 0.25MPa
Master unit: 52 Hz + OFF + OFF
Slave units: All units stop
Pe < 0.15MPa
Hot gas solenoid valve (Y1S):
(3 times per 60 min. at maximum)
Function
For systems with multi outdoor units, the control shown below is conducted on the whole
system.
Normal operation
Pe < 0.39MPa
Pe > 0.29MPa
ON
Pe < 0.07MPa
Restart standby
Pe: Value detected by the low pressure sensor
of master unit.
Low pressure standby occurs
4 times in a period of 60 min.
Stop due to malfunction
(E4 displayed)
Protection Control
100