Toshiba MMU-P0121H Service Manual page 93

Check code
[d9]
TK2 temperature detection circuit alarm
Is TK2 sensor out of place?
NO
Does TK2 sensor circuit
contact with discharge pipe?
NO
Is there miswiring of
TK1/TK2/TK3 sensor?
NO
Is resistance value characteristics
of TK2 sensor normal?
YES
Is there leakage or blockage in
peripheral circuit of oil tank? (
Leakage/blockage
Check interface P.C. board.
( * 1) Oil tank peripheral circuit leakage/blockage check procedure
1. After resetting power supply, start a trial operation.
2. Set SW01/SW02/SW03 on interface P.C. board to
1/16/1, respectively.
3. Check display on the 7 segment of interface P.C. board.
In case of judgment result "A0" "A1" → Oil level is adequate. Resume the operation.
In case of judgment result "A4" → Possibility of oil tank circuit leakage/blockage is considered
Check the following items.
4. Start a trial operation under condition that
AC220–240V, 50Hz (
power is on to SV3C valve.
5. During operation, check whether discharge gas flows
to the strainer secondary side (A part in the right
figure) at downstream of TK2 sensor circuit, and
capillary secondary side (B part in the right figure).
→ If blocked part is found, replace the part.
6. During operation, check whether leakage occurs in
the check valve (Two positions) of pipe connecting
the oil tank and compressor case.
(Check temperature of C part in the right figure.)
→ If leakage is found, replace the part.
YES
YES
YES
NO
YES
1)
*
AC220V, 60Hz )
Operation cause
1. TK2 sensor out of place, miswiring, resistance value
characteristics error
2. Oil tank peripheral circuit error
[
Check valve leakage
Capillary blockage
Strainer blockage
When operation has started
During detection of oil level
Judgment result of oil level
SV3C valve
TK1
Strainer
sensor
Capillary
B
TK2
sensor
A
C
Oil
tank
Check
SV3A
valve removal
valve
Check
valve
Balancing pipe valve
3-90
]
Modify sensor mounting.
Correct pipe so that TK2 sensor
circuit does not contact with
discharge pipe.
Modify miswiring.
TK1 sensor : CN516
[
TK2 sensor : CN515
TK3 sensor : CN507
Sensor error
Replace leaked/blockage part.
7 segment display
"OL" "– –"
"OL" "FF" or "Numeral"
"OL" "A0" "A1" or "A4"
Check joint
Capillary
Oil
separator
Strainer
Accumulator
Compressor
Check
valve
Oil
valve
Strainer
]
SV3B
valve