Service manual

12-7
CONTROL SYSTEM
SM SX DCI 1-A.3 GB
12.6 Dry Mode
As long as room temperature is higher then the set point, indoor fan will work in low speed and
compressor will work between 0 and MaxNLOADIF1C Hz.
When the room temperature is lower than the set point, compressor will be switched OFF and indoor
fan will cycle 3 minutes OFF, 1 minute ON.
12.7 Protections
There are 5 protection codes.
Normal (Norm) – unit operate normally.
Stop Rise (SR) – compressor frequency can not be raised but does not have to be decreased.
HzDown1 (D1) – Compressor frequency is reduced by 2 to 5 Hz per minute.
HzDown2 (D2) – Compressor frequency is reduced by 5 to 10 Hz per minute.
Stop Compressor (SC) – Compressor is stopped.
12.7.1 Indoor Coil Defrost Protection
ICT
ICT Trend
Fast
Increasing
Increasing No Change Decreasing Fast
ICT< -2 SC SC SC SC SC
-2 ≤ ICT<0 D1 D1 D2 D2 D2
0 ≤ ICT < 2 SR SR D1 D2 D2
2 ≤ ICT< 4 SR SR SR D1 D2
4 ≤ ICT < 6 Norm Norm SR SR D1
6 ≤ ICT ≤ 8 Norm Norm Norm SR SR
ICT> 8 Norm
12.7.2 Indoor Coil Overheating Protection
12.7.2.1 Indoor Coil Overheating Protection For 50/60/72Z
ICT
ICT Trend
Fast
Decreasing
Decreasing No Change Increasing
Fast
Increasing
ICT >62 SC SC SC SC SC
60 ≤ ICT < 62 D1 D1 D2 D2 D2
55≤ ICT <60 SR SR D1 D2 D2
52≤ ICT < 55 SR SR SR D1 D2
48≤ ICT < 52 Norm Norm SR SR D1
45≤ ICT ≤ 48 Norm Norm Norm SR SR
ICT <45 Norm
CONTENT