Protection Control - Kaisai 06RY1 Service Manual

4.7 Spray liquid cooling control
When the discharge temperature of compressor exceeds 105℃, the solenoid valve opens and the frequency of
compressor drops in order to reduce the discharge temperature. When the discharge temperature is below 100℃, the
solenoid valve closes.
If the discharge temperature exceeds 108℃ while the spray liquid cooling control is in progress, which is judged every 20s,
the frequency of compressor drops 4Hz until the minimum frequency which differs from every model. When the discharge
temperature is below 101℃, the compressor runs at the current frequency.

5 Protection Control

5.1 High Pressure Protection Control
This control protects the refrigerant system from abnormally high pressure and protects the compressor from transient
spikes in pressure.
When the discharge pressure rises above 4.3MPa the system displays P1 protection and the unit stops running. When the
discharge pressure drops below 3.6MPa, the compressor enters re-start control.
5.2 Low Pressure Protection Control
This control protects the refrigerant system from abnormally low pressure and protects the compressor from transient
drops in pressure.
When the suction pressure drops below 0.14MPa the system displays P0 protection and the unit stops running. When the
suction pressure rises above 0.3MPa, the compressor enters re-start control.
202008
Figure 3-5.1: High pressure protection control
Normal operation
P > 4.3MPa
c
High pressure protection, error code P1 is displayed
Notes:
1. P : Discharge pressure
c
Figure 3-5.2: Low pressure protection control
Normal operation
P < 0.14MPa
e
Low pressure protection, error code P0 is displayed
Notes:
1. P : Suction pressure
e
Midea CAC Confidential
P < 3.6MPa
c
P > 0.30MPa
e
M thermal Mono
Mono
21