Midea M-Thermal Series - Page 55

M‐ThermalSplit  
54 201909
MideaM‐ThermalSplitServiceManual
Procedure

H0 


Powersupplyforthemaincontrolboard
andtransformerisabnormal
1

Yes
Providenormalpowersupply
No

Thetransformerofhydronicunitis
malfunctioned
2

Yes
Replacethetransformer
No

Thereisasourceofelectromagnetic
radiationneartheunit,suchas
high‐frequencytransmitterorotherhigh
strengthradiationdevice
Yes
Removethesourceofinterference
No

CommunicationwiresPQEbetween
maincontrolboardofoutdoorunitand
hydraulicmodulehaveshortcircuited,
disconnectedormisconnected
Yes


Reconnectthecommunicationwires

No

ReplaceoutdoorunitmainPCBand
hydronicboxmainPCBinturn

Notes: 
1. Measurethevoltagesoftransformerinputportandoutport.Theinputvoltageoftransformeris220VAC,outputvoltageoftransformeris13.5VAC.Ifany
voltagesisabnormal,thepowersupplyforthemaincontrolboardofhydraulicmoduleandtransformerwillbeabnormal. 
2. Measurethevoltagesoftransformeroutputportports.Ifthevoltagesarenotnormal,thetransformerhasmalfunctioned.

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