Lennox MPB012S4S Service Manual

143
Error Code: P0
Description: IPMmoduleorIGBTovercurrentprotection.
General Note: WhenthevoltagesignalthatIPMsendstothecompressordrivechipisabnormal,thedisplayLEDwillshow“P6”andunit
willturnoff.
P6
Checkwhetherthevoltagerange
ofP-NonIPMmoduleisnormal?
277-356VDCfor18-30KBtu/h;277-
410VDCfor36KBtu/h
Checkwhethertheconnectingwiring
betweenmainboardandtheIPM
moduleisconnectedtightly.
Yes
Yes
No
Checkwhether
theinputpower
supply is cor-
rect?208-230V,
1PH,60Hz
No
No
Correcttheincom-
ingpowerproblem,
thencheckwhether
thesystemoperates
normally
Checkwhetherthe
powersupplyline
is connected cor-
rectlyandtightly.
No
Connect it correctly
andtightly,check
okornot?
Yes
No
Checkwhether
thelinesinE-
part box are con-
nectedtightly.
No
Connectittightly,
checkokornot?
NoYes
Checkwhetherthebridgerectiers
arenormal?Usethemultimeterto
measuretheresistancebetween
eachtwoterminals,checkwhether
thereistheconditionthatvalueof
resistance is 0.
Replacethe
bridgerectiers.
No
Yes
Checkwhetherthewiring
ofeachreactoriscorrect?
Replacethewiring
or reactor or replace
thePFCmodule
No
No
Connectittightly,
unit operates
correctly?
No
Yes
ReplacetheIPM
module,check
whetherthesystem
worksnormally.
No
Checkiftheoutdoor
fan runs properly
ortheoutdoorunit
ventilation is good.
ForACfanmodels,
checkwhethertheresis-
tanceofthefanmotor
is normal. If not, replace
thefanmotor.ForDC
fanmodels,refertothe
solution of fan speed
malfunction(E8).Find
outthecauseandrepair
it.
Yes
No
Replacethemainboard;
checkwhetherthesystem
operatesnormally?
No
Yes
Replacethecompressor,
checkwhetherthesystem
operatesnormally?
Problem Solved
Yes
Yes
Yes
Checkwhethertheconnectingwiring
tothecompressorisconnectedcor-
rectlyandtightly
Connectittightly,
checkokornot?
No
Yes

Lennox MPB012S4S Specifications

General

Brand	Lennox
Model	MPB012S4S
Category	Air Conditioner
Language	English