Black & Decker MUZ-FD12NA- U1, MUZ-FD09NA- U1 service manual Symptom

No.	Symptom	LED indication	Abnormal point/	Condition	Correspondence
			Condition
	Outdoor unit	7-time flash	Low discharge tem-	Temperature of discharge temperature thermistor has been	•Refer to 10-5.	"Check of LEV".
18	operates.	2.5 seconds OFF	perature protection	122 °F (50 °C) or less for 20 minutes.	•Check refrigerant circuit and refrig-
					erant amount.
		8-time flash	PAM protection PAM:	The overcurrent flows into IGBT (Insulated Gate Bipolar tran-	This is not malfunction. PAM protec-
		2.5 seconds OFF	Pulse Amplitude	sistor : TR821) or when the bus-bar voltage reaches 320 V or	tion will be activated in the following
19			Modulation	more, PAM stops and restarts.	cases;
					1 Instantaneous power voltage drop
					(Short time power failure)
					2 When the power supply voltage is
					high.
		9-time flash	Inverter check mode	The connector of compressor is disconnected, inverter check	•Check if the connector of the com-
20		2.5 seconds OFF		mode starts.	pressor is correctly connected.
					Refer to 10-5.	"How to check
					inverter/ compressor".

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