Midea MCD-18HRFN1-QRC4 Service Manual page 106

Electrical Control Function
For Compact cassette(12K)、A5(12K)
In cooling mode, indoor fan runs all the time and the speed can be selected as high, medium, low, auto and
silent.
The auto fan:
For other models:
1.3.2.4 Evaporator low temperature T2 protection.
For 12K units：
---T2<0℃, the compressor will stop and restart when T2
---0℃≦T2<4℃, the compressor frequency will be limited and decreased to the lower level
---4℃≤T2<7℃, the compressor will keep the current frequency.
---T2>7℃, the compressor frequency will not be limited.
For other units: When T2<2℃ and lasts for 3 minutes, the indoor has no capacity demand and resume till T2
≥7℃.
1.3.2.5 Condenser high temperature T3 protection
For 12K units :
---55℃<T3<60℃, the compressor frequency will decrease to the lower level until to F1 and then runs at F1.If
T3<55℃, the compressor will keep running at the current frequency.
---T3<52℃, the compressor will not limit the frequency and resume to the former frequency.
---T3>60℃ for 5 seconds, the compressor will stop until T3<52℃.
For other units: When T3≥65℃ for 3 seconds, the compressor will shut off. When T3＜52,the compressor
will restart.
112
3.5
High
3.0
Medium
1.5
1.0
Low
5.0
High
4.0
Medium
3.0
2.0
Low
>=
5℃.
Electrical Control System