Mitsumi electronic PLA-A12AA, PLA-A30AA Error Signal receiving error, Error Transmitting error

Error Code Abnormal point and detection method		Cause	Countermeasure
	Indoor/outdoor unit communication	1 Contact failure, short circuit or, ∗ Check LED display on the outdoor control cir-
	error (Signal receiving error)	miswiring (converse wiring) of	cuit board. (Connect A-control service tool,
	1 Abnormal if indoor controller board	indoor/outdoor unit connecting	PAC-SK52ST.)
	cannot receive any signal normally for 6		Refer to EA-EC item if LED displays EA-EC.
		wire
	minutes after turning the power on.		1 Check disconnection or looseness of indoor/
		2 Defective transmitting receiving
	2 Abnormal if indoor controller board	circuit of indoor controller board	outdoor unit connecting wire of indoor unit or
	cannot receive any signal normally for 3		outdoor unit.
		3 Defective transmitting receiving
E6	minutes.		Check all the units in case of twin indoor
	3 Consider the unit as abnormal under the	circuit of indoor controller board	unit system.
	following condition: When 2 or more	4 Noise has entered into indoor/	2-4Turn the power off, and on again to
	indoor units are connected to 1	outdoor unit connecting wire.	check. If abnormality generates again,
	outdoor unit, indoor controller board		replace indoor controller board or outdoor
	cannot receive a signal for 3 minutes		controller circuit board.
	from outdoor controller circuit board, a		∗ Other indoor controller board may have
	signal which allows outdoor controller		defect in case of twin indoor unit system.
	circuit board to transmit signals.
	Indoor/outdoor unit communication	1 Defective transmitting receiving 1-3Turn the power off, and on again to
	error (Transmitting error)	circuit of indoor controller board	check. If abnormality generates again,
E7	Abnormal if “1” receiving is detected 30	2 Noise has entered into power	replace indoor controller board.
	times continuously though indoor controller	supply.
	board has transmitted “0”.	3 Noise has entered into outdoor
		control wire.
	Indoor controller board	1 Defective indoor controller	1 Replace indoor controller board.
Fb	Abnormal if data cannot be normally read	board
	from the nonvolatile memory of the indoor
	controller board.
	Remote controller control board	1 Defective remote controller	1 Replace remote controller.

1Abnormal if data cannot be normally read from the nonvolatile memory of the

E1	remote controller control board.
	(Error code: E1)
or
E2	2 Abnormal if the clock function of remote
	controller cannot be normally operated.
	(Error code: E2)
	Forced compressor stop	1 Drain pump trouble	1 Check the drain pump.
	(due to water leakage abnormality)
	1 When the intake temperature subtracted	2 Drain defective	2 Please confirm whether water can be
	with liquid pipe temperature is less than	· Drain pump clogging	drained.
	-10:(14˚F), drain sensor detects	· Drain pipe clogging
	whether it is soaked in the water or not
	at the interval of 90 seconds. (Drain	3 Open circuit of drain sensor	3 Confirm the resistance of the drain sensor.
	pump will start operating when the drain	side heater
	sensor detects to be soaked in the
	water.)	4 Contact failure of drain sensor 4 Check the connector contact failure.
	2 The unit has a water leakage abnormality	connector
	when the following conditions, a and b,
	are satisfied while the above-mentioned	5 Dew condensation on drain	5 Check the drain sensor leadwire mounted.
	detection is performed.	sensor	Check the filter clogging.
PA	a) The drain sensor detects to be	· Drain water trickles along
	soaked in the water 10 times in a row.	lead wire.
(2502)
	b) The intake temperature subtracted	· Drain water waving due to filter
(2500)
	with liquid pipe temperature is detect-	clogging
	ed to be less than -10:(14˚F) for a
	total of 30 minutes. (When the drain	6 Extension piping connection	6 Check the piping connection.
	sensor detects to be NOT soaked in	difference at twin system
	the water, the detection record of a
	and b will be cleared.)
	3 The drain sensor detection is performed	7 Miswiring of indoor/ outdoor	7 Check the indoor/ outdoor connecting wires.
	in operations other than cooling. (When	connecting at twin system
	the unit stops operating, during heating
	or fan operation, when the unit stops
	because of some abnormality)	8 Room temperature thermistor /	8 Check the room temperature display of
	*Once the water leakage abnormality is	liquid pipe temperature thermis-	remote controller.
	detected, abnormality state will not be	tor detection is defective.	Check the indoor liquid pipe temperature
	released until the main power is reset.		display of outdoor controller board.

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