Toshiba MMU-P0121H Service Manual page 55

Check Detected Check code
code position name
d6 Interface TK3 sensor
alarm
d7 Interface Low oil level
detection
protection
d8 Interface TK1 temp.
detection
circuit alarm
d9 Interface TK2 temp.
detection
circuit alarm
dA Inverter Heat sink
overheating
alarm
db Interface Oil level
detection
circuit
blockage
detection
dC Interface Oil level
detection
circuit
leakage
detection
Cause
Trouble detection condition
(Position)
Temp. sensor Sensor resistance value was
(TK3) to infinity or zero (Open, Short).
detect oil level
Oil level Oil shortage status was
detection continuously detected for
circuit approx. 2 hours while oil
equalizing control was
continuously executed.
Oil level Temp. change at primary
detection side of oil tank was not
circuit detected when oil level
detection control was
executed.
Oil level Temp. change at secondary
detection side of oil tank was not
circuit detected when oil level
detection control was
executed.
IGBT Overheating of IGBT was
overheating detected.
protection
Oil level Temp. change at primary and
detection secondary sides of oil tank
circuit was not detected when oil
level detection control was
executed.
Oil level The status that TK1 temp. is
detection high (50°C or more) was
circuit continuously detected for a
long time.
3-52
Check item (Position)
• Check connector connection of TK3
sensor.
• Check characteristics of TK3 sensor
resistance value.
• Check outdoor P.C. board (interface)
error.
<Check all outdoor units in the line.>
• Check the valve to remove oil in
compressor case.
• Check for blockage in oil separator and oil
return circuits.
• Check for blockage in balancing pipe
valve and pipe between outdoor units.
• Check misconnection of TK1, TK2, and
TK3.
• Check characteristics of TK2 sensor
resistance value.
• Check leakage of reducing valve (SV3A).
• Check leakage of pressurize valve
(SV3C).
• Check for blockage of oil return valve
(SV3B).
• Check peripheral circuits of oil tank.
1) Leakage of check valve
2) Blockage of capillary
• Check for substantial refrigerant
stagnation in compressor case.
1) Check leakage of cooling bypass circuit
(PMV3).
• Check out of place of TK1 pipe sensor.
• Check characteristics of TK1 sensor
resistance value.
• Check misconnection of TK1, TK2, and
TK3.
• Check out of place of TK2 pipe sensor.
• Check characteristics of TK2 sensor
resistance value.
• Check peripheral circuits of oil tank.
1) Leakage of stop valve
2) Blockage of capillary
3) Blockage of strainer
4) Check contact of TK2 sensor circuit
with discharge pipe.
• Check misconnection of TK1, TK2, and
TK3.
• Check IGBT error.
(IGBT built-in temp. sensor error)
• Check error of outdoor fan system.
• Check for blockage in cooling duct of heat
sink.
• Check mounting failure of IGBT heat sink.
• Check for blockage of peripheral circuits of
pressurize valve (SV3C).
• Check connection of SV3C valve coil and
connector.
• Check leakage of pressurize valve
(SV3C).
• Check characteristics of TK1 sensor
resistance value.
• Check operation out of use temp. range of
outdoor unit.
(Cooling overload operation, etc.)