DIAGNOSTIC SAFETY SHUTDOWN AND TROUBLE SHOOTING
ModelMH125KTR, MH175KTR and MH210KTRheatersareequippedwithadiagnosticcontrolboardandflashingLEDerrorindicator.
ThisflashingLEDsignalsindicateunitoperationstatus.Seethefollowingdiagnosticguideforunitstatusandcorrectiveactionifnecessary.
LED
UNIT OPERATION
SteadyON
SystemCheck
SteadyOFF
OperationOK
2Flashes
Noflamedetected
3Flashes
Highlimitswitch
failure
4Flashes
CADCellFailure
PowerLight
Powertocontrol
ModelMH50KR and MH75KTR heatersareNOTequippedwithadiagnosticcontrolboardorflashingLEDerrorindicator.Seethe
followingtroubleshootingguideforunitstatusandcorrectiveactionifnecessary.
SYMPTOM
HighlimitswitchOpenCircuit
Sparks,callingforflame,but
noorslowmotoroperation
NoSpark
AbnormalMotorOperation-
MotoroverheatsorStops
UnabletoDetectFlame
FlameControlFailure
Mr. Heater, Inc. | Kerosene Forced Air Heater
TROUBLE SHOOTING
Systemperformingselftest.Noactionrequired.
Noactionrequired.
Heaterfailstostartduringthefirst30sec.ofoperation.
1.
Checkwiringtomotor(perwiringschematicinmanual).
2.
Makesurethatthepressuregaugeisinplaceandnotdamaged.
3.
Adjustpressureforproperheateroperationpermanual.
4.
WithheaterdisconnectedfromACsource,rotatefanclockwisetoverifymotorisfree.
5.
Removeairfilterhousingfrommotorandinspectthepumprotorfordamage.Ifdamaged,replacerotorassembly.
6.
Ifwiringiscorrect,pumprotorisokay,andmotorisnotrotatingfreely,replacemotororpower-packassembly.
7.
Ifproblempersists,replaceoilflamecontrolassembly.
8.
Checkforsparkarchingfromtheelectrodeassembly(ref.50),tothecombustioncylinder(ref.39).
9.
Checkthecadcell(ref.38)forcontinuity.
1.
Makesureheateriscooledoff,pressresetswitchandretry.
1.
Checkwiringtocadcell(perwiringschematicinmanual).
2.
Cleancadcellphotocell.
•
Slidecadcelloutofcadcellholder.
•
Pushthephotocelloutoftheblackrubbercadcellhousingbypushingonthe2purplewires.
•
Cleanthephotocellwithasoftclothandrubbingalcohol.
•
Pullthephotocellbackintothecadcellhousingandreinstallintoholder.
•
Testheater.
3.
Iftheheaterstilldoesnotoperate,replacecadcell.
4.
Replaceoilflamecontrolassembly.
1.
Sensingpower.Noactionrequired.
TROUBLE SHOOTING
1) Makesureheateriscooledoff,toggleswitchto"OFF"position,wait5minutesandretry.
1) Checkwiringtomotor(perwiringschematicinmanual).
2) Makesurethatthepressuregaugeisinplaceandnotdamaged.
3) Adjustpressureforproperheateroperationpermanual.
4) WithheaterdisconnectedfromACsource,rotatefanclockwisetoverifymotorisfree.
5) Removeairfilterhousingfrommotorandinspectthepumprotorfordamage.Ifdamaged,replacerotorassembly.
6) Ifwiringiscorrect,pumprotorisokay,andmotorisnotrotatingfreely,replacemotororpower-packassembly.
7) Ifproblempersists,replaceoilflamecontrolassembly.
8) Checkforsparkarchingfromtheelectrodeassembly,tothecombustioncylinder.
9)
Checkthecadcellforcontinuity.
1)
Checklengthandgageofextensioncordforproperamp.draw.(Checkrequirementsonpage4.)
2) Checkwiringtoigniter(perwiringschematicinmanual).
3) Checkgapbetweenelectrodeprobes(2.3-3mm).
4) Stillnospark,replaceigniterassembly.
5) Replaceoilflamecontrolassembly.
1) Motorspeedtoolow(Motorshouldoperateat3450rpm)-Replacemotor.
2) WithheaterdisconnectedfromACsource,rotatefanclockwisetoverifymotorisfree.
3) Removeairfilterhousingfrommotorandinspectthepumprotorfordamage.Ifdamaged,replacerotor
assembly.
4) Ifwiringiscorrect,pumprotorisokay,andmotorisnotrotatingfreely,replacemotororpower-packassembly.
5) Replaceoilflamecontrolassembly.
1) Checkwiringtocadcell(perwiringschematicinmanual).
2) Cleancadcellphotocell.
a) Slidecadcelloutofcadcellholder.
b) Pushthephotocelloutoftheblackrubbercadcellhousingbypushingonthe2purplewires.
c)
Cleanthephotocellwithasoftclothandrubbingalcohol.
d) Pullthephotocellbackintothecadcellhousingandreinstallintoholder.
e) Testheater.
3) Iftheheaterstilldoesnotoperate,replacecadcell.
4) Replaceoilflamecontrolassembly.
1) Checkwiringinheater(perwiringschematicinmanual).
2) Replaceoilflamecontrolassembly.
6
Operating Instructions and Owner's Manual