Daikin FDMQ12RVJU, Service Manual

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SiUS091601EA Control Specification
Part 4 Functions and Control 84
5.6 Freeze-up Protection Control
Outline
During cooling operation, the signal sent from the indoor unit determines the frequency upper limit
and prevents freezing of the indoor heat exchanger. The signals from the indoor unit are divided
into zones.
Details The operating frequency limitation is judged with the indoor heat exchanger temperature.
R4003644
5.7 Heating Peak-cut Control
During heating operation, the indoor heat exchanger temperature determines the frequency upper
limit to prevent abnormal high pressure.
The operating frequency limitation is judged with the indoor heat exchanger temperature.

: The valves might drop when the outdoor temperature is low to protect the compressor.
Reset zone
Up zone
Keep zone
Dropping zone
Stop zone
13°C (55.4°F)
7°C (44.6°F)
3°C (37.4°F)
0°C (32.0°F)
5°C (41.0°F)
(Reference)
Indoor heat exchanger
temperature (R2T)
Zone
Control
Stop zone When the temperature reaches the stop zone, the compressor stops.
Dropping zone The upper limit of frequency decreases.
Keep zone The upper limit of frequency is kept.
Up zone The upper limit of frequency increases.
Reset zone The upper limit of frequency is canceled.
09/12 class 15 class 18/24 class
(°C) (°F) (°C) (°F) (°C) (°F)
A 59 138.2 60 140.0 60 140.0
B

55 131.0 54 129.2 56 134.6
C

52 125.6 51 123.8 53 129.2
D

50 122.0 49 120.2 51 125.6
E 45 113.0 44 111.2 46 116.6
Indoor heat exchanger
temperature
Stop zone
Dropping zone
Keep zone
Up zone
Reset zone
(R23928)
D
C
B
A
E