Midea M-Thermal Series - Page 75

M‐ThermalSplit 
74 201909
MideaM‐ThermalSplitServiceManual
Situation3:L0orL4errorappearsafterthecompressorhasbeenrunningforaperiodoftimeandthecompressor
speedisover60rps

L0/L4 


Invertermodulehasoverheated
Yes
Repaintthethermallyconductiesilica
gelontheIPMmodule,IGBT,diode,
brigderectifer
(onthereversesideof
theinvertermodulePCB)
1

No

Invertermoduleisover‐current
2

Yes
Replacethecompressor
No

Replacetheinvertermodule
3
 
Notes: 
1. RefertoFigure4‐4.1.
2. Use clip‐on ammeter to measure the compressorcurrent, if thecurrent is normal indicatesthe invertermodule isfailed, ifthe currentis abnormal
indicatesthecompressorisfailed.
3. Whenreplacinganinvertermodule,alayerofthermallyconductivesilicagelshouldbepaintedonthePFCandIPMmodules(onthereversesideofthe
invertermodulePCB).RefertoFigure4‐4.1.


Situation4:L0errorappearsoccasionally/irregularly

L0 


Theoutdoorunitventilationisnotgood
Yes
Ensureenoughspaceforunitventilation

 
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