Midea M2OC-14HRDN1, Technical & Service Manual

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ODMI-1103-A
1. If the compressor frequency keeps lower than RECOILINFRE for Te minutes,the AC will rise the
frequency to RECOILFRE for Tf seconds and then resume to former frequency.For M4OC-36HRDN1-Q,
RECOILINFRE=45Hz, RECOILFRE=48Hz,Te=120,Tf=180; For M5OA-36HRDN1-Q, RECOILINFRE=45Hz,
RECOILFRE=48Hz, Te=90,Tf=100; For other models, RECOILINFRE=50Hz, RECOILFRE=62Hz,
Te=120,Tf=180.
2. During the Tf seconds, the EXV and indoor units keep the current running mode(except
M5OA-36HRDN1-Q model), the frequency will not be limited by the compressor discharge temp.and the
current.For M5OA-36HRDN1-Q model,the EXV will keep 300p while the indoor units will keep the current
running mode.
3. If the outdoor ambient is higher than 15
℃
during the oil return,the AC quit oil return.
7.5.9 Compressor preheating functions
----Preheating permitting condition:
If T4(outdoor ambient temperature)
＜
3 and the machine connects to power suppl
℃
y no longer than 5
seconds or if T4
＜
3 and compressor has stopped for over 3 hours, the compressor heating cable will
℃
work.
----Preheating mode:
A weak current flow through the coil of compressor from the wiring terminal of compressor, then the
compressor is heated without operation.
----Preheating release condition:
If T4
≧
5 or
℃
the compressor starts running, preheating function will stop.
7.5.10 Compressor crankcase heater
When T4<3
℃
and the compressor is not running,the crankcase heater will be active.
When T4
≧
5
℃
or the compressor starts up,the crankcase heater will stop work.(For M5OA-36HRDN1-Q,T4
≧
8
℃
)