Mitsubishi PUZ-A18NHA6 - Page 38

38
UP
(4210)
Compressor overcurrent interruption
AbnormalifovercurrentDCbusorcom-
pressorisdetectedaftercompressorstarts
operatingfor30seconds.
1Stopvalveofoutdoorunitis
closed.
2Decreaseofpowersupply
voltage
3Looseness,disconnectionor
converseofcompressorwiring
connection
4Defectivefanofindoor/outdoor
units
5Shortcycleofindoor/outdoor
units
6Defectiveinputcircuitofoutdoor
controllerboard
7Defectivecompressor
1Openstopvalve.
2Checkfacilityofpowersupply.
3Correctthewiring(U·V·Wphase)to
compressor.Referto"10-9.TESTPOINT
DIAGRAM"(Outdoorpowercircuitboard).
4Checkindoor/outdoorfan.
5Solveshortcycle.
6Replaceoutdoorcontrollercircuitboard.
7Checkcompressor.
Referto"10-6.HOWTOCHECKTHE
PARTS".
Note:Beforethereplacementoftheoutdoor
controllercircuitboard,disconnectthe
wiringtocompressorfromtheoutdoor
powercircuitboardandchecktheoutput
voltageamongphases,U,V,W,during
testrun.Nodefectonboardifvoltage
amongphases(U-V,V-WandW-U)is
same.Makesuretoperformthevoltage
checkwithsameperformingfrequency.
Abnormal point and detection method Case Judgment and action
Check Code
20
PFC/IGBT error
(Undervoltage)
•Whencompressorisrunning,
DCbusvoltagestaysat310V 
orlowerforconsecutive10
seconds
1Incorrectswitchsettingsonthe
outdoorcontrollercircuitboard
formodelselect
2Defectiveoutdoorpowercircuit
board
3Defectiveoutdoorcontroller
circuitboard
1Correctionofamodelselect
2Replaceoutdoorpowercircuitboard.
3Replaceoutdoorcontrollercircuitboard.
U9
(4220)
Detailed
codes
UF
(4100)
Compressor overcurrent interruption
(When compressor locked)
AbnormalifovercurrentofDCbusor
compressorisdetectedwithin30seconds
aftercompressorstartsoperating.
1Stopvalveisclosed.
2
Decreaseofpowersupplyvoltage
3Looseness,disconnectionor
converseofcompressorwiring
connection
4Defectivecompressor
5Defectiveoutdoorpowerboard
6 DIPSwitchsettingforselecting
modelisincorrectonthe
outdoorpowercircuitboard.
1Openstopvalve.
2Checkfacilityofpowersupply.
3 Correctthewiring(U·V·Wphase)to
compressor.Referto"10-9.TESTPOINT
DIAGRAM".(Outdoorpowercircuitboard).
4Checkcompressor.Referto"10-6.HOWTO
CHECKTHEPARTS".
5Replaceoutdoorpowercircuitboard.
6 CheckthattheDIPSwitchsettingiscor-
rectontheoutdoorpowercircuitboardby
referringto"ModelSelect"in"1)Function
ofswitches"in"10-10.FUNCTION
OFSWITCHES,CONNECTORSAND
JUMPERS".
UH
(5300)
Current sensor error
• Itisabnormalfor38Atheinputcurrentor
10secondscontinuous34Aormore.
1Defectivecircuitofcurrent
sensoronoutdoorpowercircuit
board
2Decreaseofpowersupply
voltage
1Replaceoutdoorpowercircuitboard.
2Checkthefacilityofpowersupply.
UL
(1300)
Abnormal low pressure (63L worked)
Abnormalif63Lisworked(under−4PSIG
[−0.03MPa])duringcompressoroperation.
63L:Low-pressureswitch
(A42Nonly)
1Stopvalveofoutdoorunitis
closedduringoperation.
2Disconnectionorlooseconnec-
tionofconnector(63L)onoutdoor
controllerboard
3Disconnectionorloose
connectionof63L
4Defectiveoutdoorcontrollerboard
5Leakageorshortageofrefrigerant
6Malfunctionoflinearexpansion
valve
1Checkstopvalve.
2–4Turnthepoweroffandonagaintocheck
ifF3isdisplayedonrestarting.
IfF3isdisplayed,followtheF3processing
direction.
5Correcttoproperamountofrefrigerant.
6Checklinearexpansionvalve.
Referto"10-6.HOWTOCHECKTHE
PARTS".
OCH577A