Midea M-Thermal Series - 5 Appendix to Part 4

  M‐ThermalSplit 
20190981
Procedure

PP 


Watersideheatexchangerwaterinlet/
outlettemperaturesensorisloose
1

Yes
Ensurethetemperaturesensoris
connectedproperly
No

Watersideheatexchangerwaterinlet/
outlettemperaturesensorhas
short‐circuitedorfailed
2

Yes
Replacethetemperaturesensor
No

The4‐wayvalveisblockedordamaged
3

Yes
Replacethe4‐wayvalve
No

ReplaceoutdoormainPCB  

Notes: 
1. watersideheatexchangerwaterinlettemperaturesensorandwatersideheatexchangerwateroutlettemperaturesensorconnectionsareportCN6on
thehydronicboxmainPCB(labeled11inFigure4‐2.1inPart4,2.2"MainPCBforHydronicSystem").
2. Measuresensor resistance.If the resistanceis toolow, the sensorhasshort‐circuited.Iftheresistanceisnotconsistentwith thesensor’s resistance
characteristicstable,thesensorhasfailed.RefertoPart2,1.2“Hydronic BoxLayout” and to Table 4‐5.1to4‐5.2 in Part 4, 5.1“TemperatureSensor
ResistanceCharacteristics”.
3. Restarttheunitincoolingmodetochangetherefrigerantflowdirection.Iftheunitdoesnotoperatenormally,the4‐wayvalveisblockedordamaged.

 
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