Troubleshooting by Indication on the Unified ON/OFF Controller
Troubleshooting
219
[CHECK 2] Check for causes of drop in low pressure
Referring to the Fault Tree Analysis (FTA) shown below, probe the faulty points.
Abnormally low
low-pressure
(Low evaporating
temperature)
[In cooling]
(See *1.)
Faulty low
pressure
control
Faulty
compressor
capacity
control
Faulty low pressure sensor
←
Are the electrical characteristics normal?
Faulty control PCB
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
Faulty low
pressure
protection
control
Faulty low pressure sensor
←
Are the electrical characteristics normal?
Faulty hot gas solenoid valve
←
Are the coil resistance and insulation normal?
Faulty control PCB
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
[In both cooling
and heating]
(See *2.)
[In cooling]
If the indoor unit
electronic
expansion valve is
throttled too much:
(See *3.)
Faulty indoor
unit electronic
expansion valve
Faulty valve coil
Faulty valve body
←
Are the coil resistance and insulation normal?
Faulty
control
Faulty gas pipe
thermistor of indoor unit
Faulty liquid pipe thermistor
of indoor unit
Faulty control PCB
←
Check for the thermistor resistance and connection.
←
Check for the thermistor resistance and connection.
←
Is the pressure value checked with the Service Checker
corresponding to the measurement of the pressure sensor?
Faulty outdoor
unit electronic
expansion valve
Faulty valve coil
Faulty valve body
←
Are the coil resistance and insulation
normal?
[In heating]
If the outdoor unit
electronic
expansion valve
excessively
throttled:
(See *4.)
Faulty
control
Faulty low pressure sensor
Faulty suction pipe thermistor
Faulty control PCB
←
Are the electrical characteristics normal?
←
Check for the thermistor resistance and
connection.
[In cooling]
Low suction
air temperature
of the
evaporator
[In heating]
Low suction air
temperature of
indoor unit
Short circuit
←
Is the suction air temperature not less than 14˚C
←
Is the indoor temperature not less than 14˚C
Low ambient temperature
Faulty suction air thermistor of indoor unit
←
Is the connector properly connected?
Are the thermistor resistance characteristics normal?
Low suction air temperature of outdoor unit
←
Is the outdoor temperature not less than -15˚C
Faulty outdoor temperature thermistor of outdoor unit
←
Is the connector properly connected?
Are the thermistor resistance characteristics normal?
High pipe
resistance
Abnormal piping length
Bent or crashed pipe
Clogging of foreign particles
Stop valve closed
←
Does the piping length fall in the permissible range?
←
Conduct visual checks for pipe conditions.
←
Is there any temperature difference caused before
and after the filter or branch pipe?
←
Check to be sure the stop valve is open.
Less
circulation
quantity of
refrigerant
Degradation
in condensing
capacity
Inadequate refrigerant quantity
←
Refer to P.189.
Moisture choke
←
Eliminate moisture by vacuum operation.
Dirty
evaporator
Decreased
fan airflow
rate
Decreased
fan output
Faulty fan motor
←
Can the fan motor be rotated with hands?
Are the motor coil resistance and insulation normal?
←
Is the heat exchanger clogged?
Faulty control PC board
(Including capacity setting)
←
If a spare PC board is mounted, is the
capacity setting properly made?
High air
passage
resistance
Dirty filter
←
Is there any obstacle in the air passage?
←
Is the air filter clogged?
Obstacle
*1: For details of the compressor capacity control while in cooling, refer to “Compressor PI Control” on P.50.
*2: The “low pressure protection control” includes low pressure protection control and hot gas bypass control. For details, refer to P.61.
*3: In cooling, the indoor unit electronic expansion valve is used for “superheated degree control”. (For details, refer to P.72.)
*4: In heating, the outdoor unit electronic expansion valve (EV1) is used for “superheated degree control of outdoor unit heat exchanger”.
(For details, refer to P.51.)
Faulty electronic
expansion valve
control
C: SDK04009
Panasonic
Содержание U-4..6ML5XPQ
Страница 1: ...Service Manual U 4 6ML5XPQ DPQ Urban Multi Mini UM Heat Pump ...
Страница 2: ......
Страница 12: ...Introduction x Urban Multi ML5 Mini UM Heat Pump ...
Страница 17: ...Specifications 5 Part 2 Specifications 1 Specifications 6 1 1 Outdoor Units 6 1 2 Indoor Units 10 Panasonic ...
Страница 37: ...Specifications Specifications 25 Panasonic ...
Страница 38: ...Specifications 26 Specifications Urban Multi ML5 Mini UM Heat Pump ...
Страница 39: ...Specifications Specifications 27 Panasonic ...
Страница 40: ...Specifications 28 Specifications Urban Multi ML5 Mini UM Heat Pump ...
Страница 134: ...Field Setting 122 Test Operation Urban Multi ML5 Mini UM Heat Pump ...
Страница 235: ...Piping Diagrams Appendix 223 U 4 5 6ML5DPQ 3D052712 Panasonic ...
Страница 238: ...Piping Diagrams 226 Appendix Urban Multi ML5 Mini UM Heat Pump ...
Страница 239: ...Wiring Diagrams Appendix 227 2 Wiring Diagrams 2 1 Outdoor Unit U 4 5 6ML5XPQ 3D059640 Panasonic ...
Страница 240: ...Wiring Diagrams 228 Appendix U 4 5 6ML5DPQ 3D05811B Urban Multi ML5 Mini UM Heat Pump ...
Страница 241: ...Wiring Diagrams Appendix 229 2 2 Field Wiring U 4 5 6ML5XPQ 3D057919 Panasonic ...
Страница 242: ...Wiring Diagrams 230 Appendix U 4 5 6ML5DPQ 3D052597 Urban Multi ML5 Mini UM Heat Pump ...
Страница 243: ...Wiring Diagrams Appendix 231 2 3 Indoor Unit S 20 25 32 63LM3HPQ Panasonic ...
Страница 244: ...Wiring Diagrams 232 Appendix S 40 50 80 125LM3HPQ Urban Multi ML5 Mini UM Heat Pump ...
Страница 245: ...Wiring Diagrams Appendix 233 S 20 25 32 40 50 63 80 100 125UM4JPQ Panasonic ...
Страница 246: ...Wiring Diagrams 234 Appendix S 20 25 32 40 50YM3HPQ Urban Multi ML5 Mini UM Heat Pump ...
Страница 247: ...Wiring Diagrams Appendix 235 S 25 32 40 63DM3HPS 3D039564C Panasonic ...
Страница 248: ...Wiring Diagrams 236 Appendix S 20 25NM3HPQ Urban Multi ML5 Mini UM Heat Pump ...
Страница 249: ...Wiring Diagrams Appendix 237 S 20 25 32 40 50 63FM3HPQ Panasonic ...
Страница 250: ...Wiring Diagrams 238 Appendix S80 100 125FM3HPQ Urban Multi ML5 Mini UM Heat Pump ...
Страница 252: ...Wiring Diagrams 240 Appendix S 32 63 100TM3JPR 3D039801D Urban Multi ML5 Mini UM Heat Pump ...
Страница 255: ...Wiring Diagrams Appendix 243 Panasonic ...
Страница 256: ...Wiring Diagrams 244 Appendix Urban Multi ML5 Mini UM Heat Pump ...
Страница 257: ...Wiring Diagrams Appendix 245 Panasonic ...
Страница 259: ...Option List Appendix 247 Panasonic ...
Страница 262: ...Example of Connection 250 Appendix Urban Multi ML5 Mini UM Heat Pump ...
Страница 283: ......