Toshiba SUPER MMK-AP0073H (IN) Service Manual page 98

Check code
[H06] / [20]
(Current code / AI-NET)
Are service valves of gas and
liquid pipe of outdoor unit fully opened?
Are characteristics of
low-pressure sensor normal?
Are SV2 and SV4 circuits normal?
Is not indoor unit with
different circuit connected?
In cooling season, go to (A)
In heating season, go to (B)
(A) Cooling
Does indoor fan normally
operate in cooling season?
YES
Is there clogging of indoor
Cleaning
air filter or heat exchanger?
Is indoor PMV normal?
Refrigerant shortage or
clogging or pipe deformed
(B) Heating
Is outdoor fan normally
operated in heating season?
YES
Is there clogging of
Cleaning
outdoor heat exchanger?
Is outdoor PMV normal?
Check code name
Low-pressure
protective operation
NO
YES
NO
* 1 Pressure by pressure gauge (Check joint)
YES
2 Pressure display on 7-segment display
3 Output voltage of I/F P.C. board
If 1 and 2, 3 are different, an error of pressure sensor error is considered.
If 2 and 3 are different, check I/F P.C. board.
NO
Check miscabling, misinstallation and
YES
connector connection.
YES
(Check with miscabling check function of outdoor unit.)
NO
NO
YES
NO
NO
YES
NO
YES
NO
NO
YES
1. Service valve close
2. Ps sensor error
3. SV2, SV4 circuit error
4. Miscabling of communication between indoor
and outdoor
5. Indoor/outdoor fan and condenser error
6. Indoor/outdoor PMV clogging
7. Indoor/outdoor heat exchanger clogging
8. Refrigerant shortage
Are following items concerned
to indoor fan motor normal?
1. Connector connection
2. Condenser
3. Motor
4. Fan
YES
Is connector connection
or coil normal?
YES
Is there clogging on whole valve?
NO
Is indoor fan system normal?
• Fan crack
• Fan coming-off
YES
98
Cause of operation
Open service valves fully.
Exchange low-pressure sensor.
Correct SV2 and SV4 circuits.
Correct cabling.
NO
Repair faulty parts.
Check indoor P.C. board.
Failure → Replace
NO
Repair faulty parts.
YES
Replace PMV body.
NO Check outdoor
I/F P.C. board.
Failure → Replace
Repair faulty parts.
Refrigerant shortage,
clogging, pipe deformed