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22
43
Communication failure with Unit A
●
Ƽ
●
●
44
Communication failure with Unit B
Ƽ
Ƽ
●
●
45
Communication failure with Unit C
○
○
Ƽ
●
46
Communication failure with Unit D
●
○
Ƽ
●
47
Unit A freeze protection
Ƽ
○
Ƽ
●
48
Unit B freeze protection
○
●
Ƽ
●
49
Unit C freeze protection
●
●
Ƽ
●
50
Unit D freeze protection
Ƽ
●
Ƽ
●
51 Unit
A
overheating prevention protection
○
Ƽ
Ƽ
●
52 Unit
B
overheating prevention protection
●
Ƽ
Ƽ
●
53 Unit
C
overheating prevention protection
Ƽ
Ƽ
Ƽ
●
54 Unit
D
overheating prevention protection
○
○
○
Ƽ
55
Unit A communication wire misconnection or expansion valve malfunction
●
○
○
Ƽ
56
Unit B communication wire misconnection or expansion valve malfunction
Ƽ
○
○
Ƽ
57
Unit C communication wire misconnection or expansion valve malfunction
○
●
○
Ƽ
58
Unit D communication wire misconnection or expansion valve malfunction
●
●
○
Ƽ
(1) IPM protection malfunction:
Main checking point:
●
If the input voltage of the unit is within normal range?
●
If the connection wire of compressor is connected well? Is it loose? If the connection sequence is correct?
●
If the resistance of compressor coil is normal? If the isolation of compressor coil with copper pipe is good?
●
If the unit is overloaded? If the heat radiation of the unit is good?
●
If the refrigerant charge is suitable?
7
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Note:
D
ischarge the position in below pictures with discharge resistance after open
ing
the top cover
and check if the voltage is below 20V with
a
universal meter, then begin to check.
18K:
24/30K:
