Ambient Temperature Out Of Range Protection Control; Disable Cooling Control; Inverter Module Temperature Protection Control - Midea VRF Series Service Manual

6.5 Ambient temperature out of range protection control

When the outdoor ambient temperature rises above 30.5°C heating mode is disabled to prevent the mechanical load on
compressors becoming too high and to prevent low compression ratios which can result in insufficient compressor internal
oil lubrication.
Figure 3-6.7: Disable heating control
Outdoor ambient temperature
When the outdoor ambient temperature rises above 55°C or outdoor ambient temperature drops below -16°C, cooling mode
is disabled to protect the compressor.
Figure 3-6.8: Disable cooling control
Outdoor ambient temperature
Or outdoor ambient temperature < -16
Notes:
1. If the indoor unit operates in cooling mode below -5 ° C, the temperature of the indoor unit's air outlet may be lower than 0 degrees.

6.6 Inverter Module Temperature Protection Control

This control protects the compressors from abnormally high currents and protects the inverter modules from abnormally
high temperatures. It is performed for each compressor and inverter module.
Figure 3-6.9: Inverter module temperature protection control
Ntc 100°C
≥
Inverter module temperature protection,
error code PL is displayed
Notes:
1. Ntc: Inverter module temperature
o
30.5 C
≥
o
55 C
≥
o
C
Normal operation
Ntc <80°C
Heating operation
Outdoor ambient temperature < 29
Units stop
Cooling operation
Outdoor ambient temperature < 52
Or outdoor ambient temperature≥-13
Units stop
When PL protection occurs 3 times in
100 minutes, the C7 error is
displayed. When a C7 error occurs, a
manual system restart is required
before the system can resume
operation.
V6R VRF 50/60Hz
o
C
o
C
o
C
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