3-52
Check
code
Detected
position
Check code
name
Cause
(Position)
Trouble detection condition
Check item (Position)
d6
Interface TK3 sensor
alarm
Temp. sensor
(TK3) to
detect oil level
Sensor resistance value was
infinity or zero (Open, Short).
• Check connector connection of TK3
sensor.
• Check characteristics of TK3 sensor
resistance value.
• Check outdoor P.C. board (interface)
error.
d7
Interface Low oil level
detection
protection
Oil level
detection
circuit
Oil shortage status was
continuously detected for
approx. 2 hours while oil
equalizing control was
continuously executed.
<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).
d8
Interface TK1 temp.
detection
circuit alarm
Oil level
detection
circuit
Temp. change at primary
side of oil tank was not
detected when oil level
detection control was
executed.
• Check out of place of TK1 pipe sensor.
• Check characteristics of TK1 sensor
resistance value.
• Check misconnection of TK1, TK2, and
TK3.
d9
Interface TK2 temp.
detection
circuit alarm
Oil level
detection
circuit
Temp. change at secondary
side of oil tank was not
detected when oil level
detection control was
executed.
• 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.
dA
Inverter
Heat sink
overheating
alarm
IGBT
overheating
protection
Overheating of IGBT was
detected.
• 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.
db
Interface Oil level
detection
circuit
blockage
detection
Oil level
detection
circuit
Temp. change at primary and
secondary sides of oil tank
was not detected when oil
level detection control was
executed.
• Check for blockage of peripheral circuits of
pressurize valve (SV3C).
• Check connection of SV3C valve coil and
connector.
dC
Interface Oil level
detection
circuit
leakage
detection
Oil level
detection
circuit
The status that TK1 temp. is
high (50°C or more) was
continuously detected for a
long time.
• 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.)
