Toshiba MMU-AP0091H 155, P04 Actuation, P05 / AF Open phase, negative phase, High-pressure SW

Check code	Check code name		Cause of operation
[P04] / [21]	Actuation of	1. High-pressure SW error
(TCC-L / AI-NET)	high-pressure SW	2. Service valve closed
		3.	Pd sensor error
		4.	Indoor/outdoor fan error
		5.	Indoor/outdoor PMV choke
		6.	Indoor/outdoor heat exchanger clogging, air short circuit
		7.	SV2 circuit error
		8.	SV4 circuit error
		9.	SV5 circuit error
		10. Discharge line check valve malfunction
		11. Refrigerant overcharge

A									C All heating operation
Is SV4 circuit normal?			NO		Repair SV4 circuit.
					Coil error, clogging,
	YES			( disconnection of wiring, etc. )
									All heating operation
Refrigerant overcharge,
clogging,pipe breakage,
abnormal overload condition								YES	Does heating indoor fan
									normally operate?
						NO	Is connector	NO		NO
			Is indoor
							connection,
		PMV normal?
							coil normal?

Sub-code:01: Compressor 1 side		02: Compressor 2 side			Note)
			NO
Does high-pressure SW operate?				Is circuit cabling normal?
	YES				YES

High-pressure SW is normally closed. (B contact)

NO

Check and correct cabling.

Check I/F P.C. board.

Failure ÆReplace

		YES	YES
	Are there any			Repair
				faulty parts.
YES	obstructions in the operation
	of the indoor heat exchanger?
	1 Air filter clogging
	2 Heat exchanger clogging			Are connector connection,	NO
	3 Air short circuit
				heat exchanger, fan, and
		NO		fan motor normal?

155

Are parts of high-pressure SW normal?

YES

Is service valve fully opened?

YES

Check for mispiping of

discharge/suction gas main pipes.

Normal

Check operation of PMV3 SV12 valve.

Normal

Is the flow selector normal?

Normal

Reset power supply, and start a test operation corresponding to the season.

Are characteristics of

high-pressure sensor normal?

B All cooling operation

Does cooling outdoor fan normally operate?

YES

NO

NO

Abnormal

Abnormal

Abnormal

All cooling operation To	B
All heating operation ÆTo	C

NO	Is there no crack or		NO
	coming-off of fan?
		YES

Check parts.

Failure ÆReplace

Open service valve fully.

Correct piping.

Replace defective parts.

Repair the flow selector unit.

Replace the high-pressure sensor.

Repair faulty parts.

Connector connection,

fan IPDU, fan motor, wiring

Eliminate the								YES
interfered causes.										Repair
										faulty parts.
	NO	Is 4-way valve normal?
								Are characteristics of TC2 NO
				YES
								and TCJ sensor resistance
Replace 4-way valve.								value normal?
								YES
	NO
		Is SV11 circuit normal?							Replace TC2
									or TCJ sensor.
				YES
Repair faulty position.							NO
				Is there clogging
								Check indoor P.C. board.
				of the valve?				Failure ÆReplace
	NO				YES
									Replace PMV body.
		Are indoor units of different
		refrigerant circuit connected?
			YES	Check with miscabling check
				( function of outdoor unit.		)
Check and								Refrigerant overcharge, clogging,
correct the cabling.								pipe breakage, abnormal overload condition

Are there any obstructions in the operation of the indoor heat exchanger?		YES
1.	Air filter clogging
2. Heat exchanger clogging
3.	Air short circuit

NO

NO

Is SV2 circuit normal?

YES

A

Eliminate the interfered causes.

Repair SV2 circuit.

( Coil error, clogging, ) disconnection of wiring, etc.

Check code Check code name Cause of operation

	[P05] / [AF]	Open phase, negative phase	1.	Power supply open phase
	(TCC-L / AI-NET)		2.	Power supply negative phase
• Check the phase power line of outdoor unit.
•	Check error of outdoor I/F P.C. board.
•	Check there is no looseness, etc of terminal.