Toshiba MiNi-SMMS MCY-MAP0501HT Service Manual page 141

Check code Check code name
[P20] / [22] High-pressure protective operation
(TCC-L / AI-NET)
NO
Are service valves fully opened?
YES
NO
Are characteristics of
high-pressure sensor normal?
YES
Cooling operation ® To B
Reset power supply, and start a test
operation corresponded to the season.
Heating operation ® To C
* 1. Pressure by pressure gauge (Check joint)
2. Pressure display on 7-segment display
3. Output voltage of I/F P.C. board
B Cooling operation
If 1 and 2, 3 are different, an error of pressure sensor is considered.
If 2 and 3 are different, check I/F P.C. board.
NO
Does cooling outdoor fan normally operate?
YES
YES
Is there no fan crack or coming-off?
NO
NO
Is outdoor PMV normal?
YES
Are there any obstructions to the
YES
operation of the heat exchanger?
1. Blocked heat exchanger
2. Air short circuit
NO
NO
Is SV2 circuit normal?
YES
NO
Is SV4 circuit normal?
YES
NO
Does the check valve of the main
discharge pipe operate normally?
YES
Refrigerant overcharge, clogging,
pipe breakage, abnormal overload condition
Cause of operation
1. Pd sensor error
2. Service valve closed.
3. Indoor/outdoor fan error
4. Indoor/outdoor PMV clogging
5. Indoor/outdoor heat exchanger clogging
6. SV2 circuit error
7. SV4 circuit error
8. SV5 circuit error
9. Outdoor I/F P.C. board error
10. Operation error of check valve of main
discharge pipe
11. Refrigerant overcharge
Open service valves fully.
Check parts.
Failure ® Replace
Correct faulty parts.
Correct faulty parts.
(Connector connection, fan IPDU, fan motor, wiring)
Correct faulty position.
(Connector connection wiring, coil mounting, valve clogging, etc)
Eliminate the interfered causes.
Repair SV2 circuit.
(Coil error, clogging, disconnection of cable, etc.)
Repair SV4 circuit.
(Coil error, clogging, disconnection of cable, etc.)
Repair check valve. ® Replace
C
All heating operation
NO
Does heating indoor fan
normally operate?
YES
NO
Is the PMV Kit used?
YES
YES
Is indoor PMV normal?
NO
Is the PMV built in the PMV built in the indoor
indoor unit made full open? unit is made full open.
YES
Is the connection cable
NO
between PMV Kit and indoor unit Connection
connected certainly?
YES
NO
Is the PMV of "PMV Kit" normal ?
YES
Is connection or coil normal?
YES
Is check valve of main NO
discharge pipe normal?
YES
Is there clogging of valve?
the
YES
Are there
any obstructions to the
YES
operation of the heat exchanger?
1. Air filter clogging
2. Blocked heat exchanger
3. Air short circuit
NO
NO
Is SV5 circuit normal?
YES
Abnormal
Check operation of 4-way valve.
Normal
NO
Are there indoor units connected
to different refrigerant circuits?
( Use the mis-wiring check function
of outdoor unit.
YES
Refrigerant overcharge,
clogging, pipe breakage,
abnormal overload condition
Is connector
NO
connection of indoor
heat exchanger fan or
fan motor normal?
YES
Repair faulty parts.
NO
Are characteristics
NO
of sensor TC2 and TCJ
resistance normal?
YES
Replace TC2
or TCJ sensor.
NO
Repair faulty parts.
Repair check valve. → Replac
NO ®
Check indoor P.C. board.
Faulty Replace
Replace PMV body.
Eliminate the interfered causes.
Repair SV5 circuit.
( Coil error, choke,
disconnection of cable, etc.
Replace 4-way valve.
Check and correct cabling.
)
)