Mitsumi electronic service manual HOW TO CHECK THE PARTS PKA-A12HA4 PKA-A18HA4, Thermistor

9-6. HOW TO CHECK THE PARTS PKA-A12HA4 PKA-A18HA4

Parts name								Check points
Room temperature				Disconnect the connector then measure the resistance with a tester.
thermistor		(TH1)		(At the ambient temperature 50"F~86"F)
Liquid pipe thermistor
		(TH2)		Normal			Abnormal		(Refer to the next page for a detail.)
Condenser/evaporator				4.3k~9.6k		Open or short
temperature thermistor
		(TH5)
Vane motor (MV)				Measure the resistance between the terminals with a tester. (Coil temperature 77"F)
Red		M				Normal				Abnormal
Yellow				-		-	-	-
Brown				Brown-Red	Brown-Orange		Brown-Yellow	Brown-Green		Open or short
	Orange Green
Connect pin No.						350 ± 7%
	
Fan motor (MF)			Refer to 9-6-2.

9-6-1. Thermistor

<Thermistor Characteristic graph>

		Room temperature thermistor (TH1)
	Thermistor for
		Pipe temperature thermistor/liquid (TH2)
	lower temperature
		Condenser/evaporator temperature
		thermistor (TH5)
Thermistor R0=15k		± 3%
Fixed number of B=3480 ± 2%
		1			1
t( )Rt=15exp { 3480(							) }
			273+t		273
			1			1
			273+	T-32	273
		1.8

0

10

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40

Resistance (k )

<Thermistor for lower temperature>

50

40

30

20

10

0

-20 -10 0 10 20 30 40 50 °C -4 -14 32 50 68 86 104122 °F

Temperature

22