Model # COMPACT UNIT HEATER

WARNING: Improper installation, adjustment, alteration, service or maintenance can cause injury or property damage. Refer to this manual. For assistance or additional information consult a qualified installer, service agency or the gas supplier.

—WHAT TO DO IF YOU SMELL GAS • DO NOT try to light any appliance. • DO NOT touch any electrical switch; do not use any phone in your building. • Leave the building immediately

• Immediately call your gas supplier from a phone remote from the building. Follow the gas suppliers instructions.

• If you cannot reach your gas supplier, call the Fire Department.

-- Installation and service must be performed by a qualified installer, service agency or the gas supplier.

FOR YOUR SAFETY: Do not store or use gasoline or other flammable vapors and liquids in the vicin-ity of this or any other appliance.

WARNING: If the information in these instructions are not followed exactly, a fire or explosion may result causing property damage, personal injury or loss of life.

201760185

OPERATINGINSTRUCTIONSANDOWNER’SMANUAL

READ INSTRUCTIONS CAREFULLY:Readandfollowallinstructions.Placeinstructionsinasafeplaceforfuturereference.Donotallowanyonewhohasnotreadtheseinstructionstoassemble,light,adjustoroperatetheheater.

Model#

www.mrheater.com •800-251-0001

MHU50MHU80MHU125

®

COMPACT UNIT HEATERFOR RESIDENTIAL/COMMERCIAL USE

CompactUnit/UtilityHeater OperatingInstructionsandOwner’sManual2

WARNING: FIRE OR EXPLOSION HAZARDFailuretofollowsafetywarningsexactlycouldresultinseriousinjury,deathorpropertydamage.Besuretoreadandunder-standtheinstallation,operation,andserviceinthismanual.Improperinstallation,adjustment,alteration,serviceormainte-nancecancauseseriousinjury,deathorpropertydamage.

WARNING: FIRE,BURN,INHALATION,ANDEXPLOSIONHAZARD.

KEEPSOLIDCOMBUSTIBLES,SUCHASBUILDINGMATERIALS,PAPERORCARDBOARD,ASAFEDISTANCEAWAYFROMTHEHEATERASRECOMMENDEDBYTHEINSTRUCTIONSNEVERUSETHEHEATERINSPACESWHICHDOORMAYCONTAINVOLATILEORAIRBORNECOMBUSTIBLES,ORPRODUCTSSUCHASGASOLINE,SOLVENTS,PAINTTHINNER,DUSTPARTICLESORUNKNOWNCHEMICALS.

CONTENTSUNITDIMENSIONS.................................................................. 3

SHIPPING................................................................................. 4

REQUIREMENTS....................................................................... 4

UNITHEATERINSTALLATION.................................................... 5

COMBUSTION&VENTILATIONAIR.......................................... 5

VENTING...............................................................................5-9

ELECTRICALCONNECTIONS..................................................... 9

GASCONNECTION.................................................................10

LEAKCHECK...........................................................................10

START-UPOPERATION.............................................................10

HEATINGSEQUENCEOFOPERATION...................................... 11

IGNITIONCONTROLLED......................................................... 11

ADJUSTMENTS........................................................................12

SERVICE..................................................................................12

WIRINGDIAGRAM..................................................................13

FUELCONVERSION.......................................................... 14-18

PARTSLIST..............................................................................19

WARRANTY............................................................................22

THE STATE OF CALIFORNIA REQUIRES THE FOLLOWING WARNINGS:

WARNING: Combustionby-productsproducedwhenusingthisproductcontaincarbonmonoxide,achemicalknowntotheStateofCaliforniatocausecancerandbirthdefects(orotherreproductiveharm).

WARNING: Thisproductcontainschemicals,includinglead,knowntotheStateofCaliforniatocausecancerandbirthdefectsorotherreproductiveharm.

LANGUAGESENGLISH..............................................................................1-22

SPANISH............................................................................23-45

FRENCH.............................................................................46-68

GENERAL INFORMATIONRETAINTHISMANUALFORFUTUREREFERENCE.FORQUESTIONS,PROBLEMS,MISSINGPARTSBEFORERETURNINGTORETAILERPLEASECALLWITHMODELNUMBERANDSERIALNUMBEROFHEATER:1-800-321-0001

MONDAY-FRIDAY8-5PMEASTERNTIMEORE-MAILUSINGTHEMR.HEATERWEBSITE:WWW.MRHEATER.COM

InordertoprovidethebestservicepossibleMr.Heaterisnowgivingyoumorewaystogetintouchwithus:

WEBSITE:Mr.Heater’sfulllineofproductarenowat: WWW.MRHEATER.COM

FACEBOOK:FindusonFacebook

TWITTER:Findusontwitter

YouTube:TherearenowinformationalvideosonYouTube.

WARNING:Yoursafetyisimportanttoyouandtoothers,sopleasereadtheseinstructionsbeforeyouoperatethisheater

125K unit 80K Unit 50K Unit

V/A/H/Phase 120v/3a/60hZ/1Φ 120v/2.3a/60hZ/1Φ 120v/2.3a/60hZ/1Φ

BTU Input 125,000BTU 80,000BTU 50,000BTU

BTU output 100,000BTU 64,000BTU 40,000BTU

Efficiency % 80% 80% 80%


UNIT DIMENSIONS (N-NATURAL GAS, P-PROPANE)

SIDE VIEW

SERVICE ACCESS PANEL

HANGING BRACKETS (2)

ADJUSTABLE LOUVERS

TOP VIEW

MOUNTING SLOTS (Typical) 5/16 x 3 Inches (8 x 76 mm)

HANGING BRACKETS

AIR FLOW

HEAT EXCHANGER (ALUMINIZED STEEL)

START–UPANDPERFORMANCECHECKLIST JobName:__________________________________________

JobLocation:________________________________________

Installer:____________________________________________

UnitModelNo.:______________________________________

ElectricalConnectionsTight?_______________________________________________

SupplyVoltage___________________________________________________________

GasPipingConnectionsTight&Leak-Tested?__________________________________

MotorAmps_____________________________________________________________

FurnaceBtuInput________________________________________________________

LinePressure____________________________________________________________

ManifoldPressurew.c. ____________________________________________________

JobNo.:______________________________________

City:_________________________________________

City:_________________________________________

SerialNo.:_____________________________________

Date:_______________________________________

State/Province:_______________________________

State/Province:_______________________________

ServiceTechnician:____________________________

FlueConnectionsTight?__________________________________________________

FanTimerOperationChecked?_____________________________________________

THERMOSTAT

Calibrated?_____________________________________________________________

HeatAnticipatorProperlySet?

Level?_________________________________________________________________

Dimension 50 80 125

A 12(305) 17(432) 24.67”(626.8)

B 5.5”(140) 6.5”(165) 8.08”(205.25)

C 4.25”(108) 6.75”(171) 9.43”(239.61)


SHIPPINGTheheateriscompletelyassembled.Installationinstructions,twomountingbrackets(shippedloose),andafluetransitionareincluded.Checktheunitforshippingdamage.Thereceivingpartyshouldcontactthelastcarrierimmediatelyifanyshippingdamageisfound.

REQUIREMENTS–CSAINTHEUSAInstallationofgasunitheatersmustconformwithlocalbuildingcodesor,intheabsenceoflocalcodes,withthecurrentNationalFuelGasCodeANSIZ223.1.

InstallationinaircrafthangersmustbeinaccordancewiththecurrentStandardforAircraftHangersANSI/NFPANo.409.

InstallationinparkingstructuresmustbeinaccordancewiththecurrentStandardforParkingStructuresANSI/NFPANo.88A.

InstallationinrepairgaragesmustbeinaccordancewiththecurrentStandardforRepairGaragesANSI/NFPANo.88B.

Theseunitsareapprovedforresidentialapplications.Forinstallationinaresidentialgaragetheseunitsmustbeinstalledsothatthebottomoftheheaterislocatednolessthan8feet(2.438m)abovefloor.Heatermustbelocatedorprotectedtoavoidphysicaldamagebyvehicles.RefertotheNationalFuelGasCode,ANSIZ223.1,currentedition.

AuthoritieshavingjurisdictionshouldbeconsultedbeforeNFPAinstallation.AirforcombustionandventilationmustconformtothemethodsoutlinedinANSIZ223.1,section5.3,AirforCombustionandVentilation,orapplicableprovisionsoflocalbuildingcodes.TheNationalFuelGasCodeisavailablefrom:

AmericanNationalStandardInstituteInc.11West42ndStreetNewYork,NY10036

TheseunitsareCSAInternationaldesigncertified.Theseunitheatersarecertifiedforinstallationtocombustiblematerialaslistedintable1andonunitratingplate.Accessibilityandserviceclearancesmustbeobservedinadditiontofireprotectionclearances.

AllelectricalwiringandgroundforunitmustbeinaccordancewiththeregulationsofthecurrentNationalElectricCodeANSI/No.70.

TheNationalElectricCodeisavailablefrom:

NationalFireProtectionAssociation 1BatterymarchPark POBox9101 Quincy,MA02269-9101

REQUIREMENTS–CSAINCANADATheinstructionsareintendedonlyasageneralguideanddonotsupersedelocalcodesinanyway.Authoritieshavingjurisdictionshouldbeconsultedbeforeinstallation.Theinstallationmustconformwithlocalbuildingcodesorintheabsenceoflocalcodes,withthecurrentCSAB149.1,NaturalGasandPropaneInstallationCode.AllelectricalwiringandgroundingfortheunitmustalsocomplywiththeCanadianElectricalCodeCSAC22.1,currentedition.

TheseheatersareCSAInternationalcertifiedfortheclearancestocombustiblemateriallistedontheratingplateandtable1.Provideadequateclearancearoundairopeningsintothecombustionchamber,clearancesfromcombustiblematerial,andprovisionsforaccessibilityandforcombustionandventilationairsupply.Provisionshallbemadeforserviceaccessibilitytotheheater.Notethatfireprotectionclearancesmaybeexceededtoprovideadditionalspaceforserviceandaccessibility.

GARAGE INSTALLATIONS:InstallationinparkingstructuresmustbeinaccordancewiththecurrentStandardforParkingStructuresANSI/NFPANo.88A.

InstallationinrepairgaragesmustbeinaccordancewiththecurrentStandardforRepairGaragesANSI/NFPANo.88B.

1. Inastoragearea,clearancefromheaterstocombustiblematerialsmustbesuchthatthematerialshallnotattainatemperatureabove160°Fbycontinuousoperationoftheunit.

2. Eightfootminimumclearancefromthefloortothebottomoftheheatermustbemaintained.RefertotheCSAB149.1,NaturalGasandPropaneInstallationCode

AIRCRAFT HANGER:Installationofgasunitheatersmustconformwithlocalbuildingcodesor,intheabsenceoflocalcodes,withthecurrentNationalFuelGasCodeANSIZ223.1.

1. Inanareawhereaircraftarehousedorserviced,10’minimumclearancefromhighestsurfaceofaircrafttobottomoftheheatermustbemaintained.

2. Inotherareas,8’minimumclearancefromthefloortobottomofheatermustbemaintained.

3. Heatersshouldbelocatedsoastobeprotectedfromdamagefromaircraftorotherappliancesneededforservicingofaircraft.Refertorequirementsoftheenforcingauthorities.

TABLE 1 UNIT CLEARANCES

Top Sides AccessPanel

Bottom Rear SingleWallVent*

in mm in mm in mm

1 25 1 25 18 457

in mm in mm in mm

0 0 18 456 6 152

*Exceptforlistedclearancethimbles.


Theseunitsarecertifiedforresidentialapplications.Forinstallationinaresidentialgarage,theseunitsmustbeinstalledsothatburnersandignitionsourcearelocatednolessthan18”(457mm)abovefloor.Heatermustbelocatedorprotectedtoavoidphysicaldamagebyvehicles.RefertoCSAB149.1,NaturalGasandPropaneInstallationCodecurrentedition.

INCANADA:Inaconfinedarea,theheatermustbeinstalledinaccordancewiththeCSAB149.1,NaturalGasandPropaneInstallationCode.Besuretocheckwithlocalcodesandordinancesforadditionalrequirements.

UNIT HEATER INSTALLATIONUnitisshippedreadyforinstallation.Unitmaybeinstalledasshowninfigure 1orinverted180odependingondesiredlocationasgovernedbyclearances,ventconnection,airdirection,gassupply,electricalsupplyandserviceaccessibility.

1. Ifinstallingunitinaninvertedposition:Removeandretainscrewssecuringdoorandrotatedoor180o.Securewithretainedscrews.Rotatelouversdirectingairflowasdesired.

2. Chooselocationformountingbrackets.

3. Removeandretainthreescrewsalongtopedge(bottomedgewheninverted)offrontofunit.

4. Alignscrewholesonmountingbracketwithholesalongtopedge(eitheruprightorinverted)ofunit.Secureonemountingbrackettofrontofunitwithretainedscrews.Secureothermountingbrackettobackofunitwithscrewsretainedonthebackofunit.

5. Tosupportunit,securemountingbrackettoceilingjoistortruss.Unitmayalsohangonrodsasshowninfigure 1.

COMBUSTION AND VENTILATION AIRAdequatefacilitiesforsupplyingairforcombustionandventilationmustbeprovidedinaccordancewiththelatesteditionofsection5.3,AirforCombustionandVentilation,oftheNationalFuelGasCode,ANSIZ223.1,intheU.S.A.,CSAB149.1NaturalGasandPropaneInstallationCode,orapplicableprovisionsoflocalbuildingcodes.

Allgasfiredappliancesrequireairtobeusedforthecombustionprocess.Inmanybuildingstoday,thereisanegativeindoorairpressurecausedbyexhaustfans,etc.Ifsufficientquantitiesofcombustionairarenotavailable,theheateroranotherappliancewilloperateinaninefficientmanner,resultinginincompletecombustionwhichcanresultintheproductionofexcessivecarbonmonoxide.

CAUTION: Insufficientcombustionaircancauseheadaches,nausea,dizziness,asphyxiationordeath.

Ifindoorairistobeusedforcombustion,itmustbefreeofthefollowingsubstancesorthelifeoftheheatexchangerwillbeadverselyaffected:chlorine,carbontetrachloride,cleaningsolvent,halogenrefrigerants,acids,cementsandglues,printinginks,fluorides,paintremovers,varnishes,oranyothercorrosives.

VENTING

A–GENERALRECOMMENDATIONSANDREQUIREMENTS

NOTE:Theventisapassageway,verticalornearlyso,usedtoconveyfluegasesfromanappliance,oritsventconnector,totheoutsideatmosphere.Theventconnectoristhepipeorductthatconnectsafuel-gasburningappliancetoaventorchimney.

Unitheatersmustbeventedincompliancewithalllocalcodesorrequirementsofthelocalutility,thecurrentstandardsofthe(American)NationalFuelGasCode,ANSIZ223.1or(Canada)CSAB149.1NaturalGasandPropaneInstallationCode,andthefollowinginstructions.

Ametalstamped/extrudedtransitionissuppliedwiththiscertifiedunit.Itmustnotbemodifiedoralteredandmustbeinstalledontheoutletoftheinduceddraftblowerassemblypriortotheinstallationoftheventorventconnector.Failuretocomplywiththisrequirementwillvoidthecertificationoftheunitbytheapprovalagencies.Alljointsshallbesecuredwithatleasttwocorrosionresistantscrews.Alljointsmustbecheckedforgastightnessafterinstallation.

B–VERTICALVENTSUSINGMETALVENTPIPE–COMMERCIALANDRESIDENTIALINSTALLATIONS

MHUcompactunitheatersarelistedasCategoryIappliancesforverticalventinstallations.

1. MHUunitheatersaretobeusedwithNFPA-orANSI-approvedchimneys,U.L.listedtypeB-1gasvents,singlewallmetalpipe,orlistedchimneyliningsystemforgasventingwhereapplicable,aswellasthemodificationsandlimitationslistedinfigure 2.SealsinglewallventmaterialaccordingtothesectionA - General Recommendations and Requirements.

2. Theventconnectorshallbe3”(76mm)diameteron50kunitsand4”(102mm)diameteron80&125kunits.Inallcases,afluetransitionpiece(supplied)isrequiredtofitovertheoutletoftheinduceddraftassemblyontheappliance.

3. Keeptheventconnectorrunsasshortaspossiblewithaminimumnumberofelbows.Refertothe(American)NationalFuelGasCodeANSIZ223.1or(Canada)CSAB149.1NaturalGasandPropaneInstallationCodeformaximumventandventconnectorlengths.Horizontalrunoftheventconnectorfromtheinduceddraftblowertothechimney/vent

INSTALL UNIT / UTILITY HEATER

SUPPORT RODSMOUNTING

BRACKETS (2)

FIGURE 1


C–HORIZONTALVENTING–GENERALDuetochangestoZ83-82009CSA2.6-2009,theuseofsinglewallB-Ventisnolongerpermittedasanacceptablematerialwhenventinghorizontally,thischangecoversbothresidentialandcommercialinstallations.AllhorizontallyventedunitsmanufacturedafterJulyof2011mustbeventedasaCateroryIIIUnit/UtilityHeaterincompliancewithUL1738&ULS636.Commonventingisnotallowedwhenhorizontallyventingtheunitheater.

Theminimumhorizontalventlengthis5feet(914mm).

1. Ifpossible,donotterminatethehorizontalventthroughawallthatisexposedtoprevailingwind.Exposuretoexcessivewindscanaffectunitperformance.

2. Ventterminationmustbefreefromobstructionsandatleast12”(306mm)abovegradelevelandmaximumsnowheight.

3. Donotterminateventdirectlybelowroofeavesoraboveawalkway,oranyotherareawherecondensatedrippingmaybetroublesomeandmaycausesomestaining.Avoidwindowswheresteammaycausefoggingoricebuildup.

4. Whenhorizontallyvented,minimumclearanceforterminationfromanydoor,window,gravityairinlet,gasorelectricmeter,regulators,andreliefequipmentis4ft.(1.2m)forU.S.installations.RefertoNFPA54/ANSIZ223.1intheU.S.A.andCSAB149.1NaturalGasandPropaneInstallationCodeand.2inCanadaorwithauthoritieshavinglocaljurisdiction.InCanada,ventterminationmusthaveaminimum6ft.(1.8m)horizontalclearancefromgasandelectricmetersandreliefdevicesasspecifiedintheCanadianB149.1,NaturalGasInstallationCode.

cannotexceedthevaluesintable 2.

4. Whenthelengthofasinglewallvent,includingelbows,exceeds5feet(1.5m),theventshallbeinsulatedalongitsentirelengthwithaminimumof1/2”thickfoilfacedfiberglass1-1/2#densityinsulation.Ifasinglewallventisusedinanunheatedareaitshallbeinsulated.Failuretodosowillresultincondensationoffluegases.

5. Theunitmaybeventedverticallyasasingleapplianceorasacommonventwithothergas-firedappliances.Incommonventingsituations,ventconnectorsforotherappliancesmustmaintaina4”(100mm)verticalseparationbetweentheventconnectors.Refertocommonventingtablesinthe(American)NationalFuelGasCodeANSIZ223.1or(Canada)CSAB149.1NaturalGasandPropaneInstallationCodeforproperventsize.

6. Clearancetocombustiblematerialis6”(152mm)forsinglewallventmaterialexceptwherealistedclearancethimbleisused.ClearancetocombustiblematerialfortypeB-1ventorfactory-builtchimneyispermanufacturer’sinstructions.

7. Theventconnectorshallbesupportedwithoutanydipsorsags.Verticalventsshallbesupportedinaccordancewiththeirlistingandmanufacturers’instructions.Allhorizontalventconnectorrunsshallhaveaslopeuptotheverticalventofatleast1/4”perfoot(1mmper50mm).

8. AllverticaltypeB-1vents,singlewallvents,orlistedchimneyliningsystemmustbeterminatedwithalistedventcaporlistedroofassembly.

9. Theventmustextendatleast3’(1m)abovethehighestpointwhereitpassesthrougharoofofabuildingandatleast2’(0.6m)higherthananypartofabuildingwithinahorizontaldistanceof10’(3.05m)unlessotherwisespecifiedbythe(American)NationalFuelGasCode,ANSIZ223.1or(Canada)CAN/CGA-B149InstallationCode.Theventmustextendatleast5’(1.6m)abovethehighestconnectedequipmentfluecollar.

FIGURE 2

VENT TERMINATION ON SINGLE WALL VENT

SINGLE WALL TERMINATION

DOUBLE WALL (TYPE B-1) TERMINATION

ROOF FLASHING

ROOF PITCHEDFROM 0”TO 45”

2” CLEARANCETHIMBLESHALL NOT BE A

CONCEALED SPACE

ROOF FLASHING

ROOF PITCHEDFROM 0” TO 45”

12”MAXCLEARANCE TO BE AS

SPECIFIED ON TYPE“B”VENT PIPE

SEAL JOINT BETWEEN SINGLE WALL VENTAND “B”VENTAND THE ANNULAR SPACE OF THE “B”VENT

No.of Feet m Elbows

1 25 7.6

2 20 6.1

3 15 4.6

4 10 3.0

5 5 1.5

Maximumlengthofventconnectornottoexceed30ft.(9.1m).

TABLE 2MAXIMUM HORIZONTAL VENT

LENGTHS


5. Ventterminationmustbeaminimumof4’(1.2m)belowor4’(1.2m)horizontallyfromanysoffitventorunder-eavevent.

6. Ventmustbeaminimumof6’fromaninsidecornerformedbytwoexteriorwalls.Ifpossible,leavea10’clearance.

7. Ventterminationmustbeaminimumof10’(3m)fromanyforcedairinlet(includesfreshairinletforotherappliances,suchasadryer).

8. Whenterminationisroutedthroughanexteriorcombustiblewalltheventmustbesupportedusingalistedclearancethimble.Sealtheconnectionbetweenthesinglewallanddoublewallpipesandtheannularspaceofthedoublewallpipeasshowninfigure2.Insideedgeofventterminationteemustbeatleast12inchesfromoutsidewallasshowninfigure 3.

9. Forhorizontalventing,theventpipeshallbesupportedwithhangersnomorethan3ft.(1m)aparttopreventmovementafterinstallation.

D–HORIZONTALVENTING–COMMERCIAL1. Horizontalcommercialinstallationsareforbuildingswhich

arenotattachedtolivingspaces.Theventmaybesinglewallventmaterialinstalledaccordingtothesections

Venting A - General Recommendations and Requirements andC - Horizontal Venting General andD - Horizontal Venting - Commercial. Refertofigure 3.

2. Theventpipediameterforhorizontalcommercialinstallationsshallbe4”(76mm)on50units.Becauseofthisatransitionpiecehasbeensuppliedandisalreadyattachedtoyourheater.Refertofigure4

3. Selectawallterminationpointthatwillmaintain1/4”riseperfootslopeofhorizontalrunofventpipe.

4. Forupwardslopedventacondensateteeanddrainmustbeinstalledwithinthefirst5’(1.5m)fromtheunitheatertoprotecttheappliance.Ifaflexiblecondensatedrainlineisused,thedrainlinemustincludealoopenteringthe

structure.Iftheunitisshutdownforanextendedperiodoftimeandwillbeexposedtosub-freezingtemperatures,thecondensatemayfreeze.

E–HORIZONTALVENTING–RESIDENTIAL1. Forhorizontalresidentialinstallationstheseunitsare

certifiedasCategoryIIIappliances.Venting A - General Recommendations and Requirements andC - Horizontal Venting General andE - Horizontal Venting - Residential.

Refertofigure 6.

2. Theventpipediameterforhorizontalresidentialinstallationsshallbe4”onallunits.Astandardventtransitionisrequiredatunitinadditiontothetransitionsuppliedwiththeunit.

3. Themaximumventlengthis25’(7.6m)plusone90-degreeelbow.Theminimumlengthis5’(1.5m).

4. Theventmustmaintaina1/4¼”riseperfootofslopeupwardstowardthetermination.

FIGURE 3

CONDENSATE DRAIN THROUGH TEE PIPE AND DRAIN LOOP UPWARD SLOPE ON HORIZONTAL VENT-COMMERCIAL INSTALLATION

CATEGORY III VENT ACCORDING TO THESE INSTALLATION INSTRUCTIONS. SLOPE: + 1/4 INCH FOR 1 FOOT RUN MINIMUM.

DRAIN LOOP WITH WATER TRAP (TO CONDENSATE DRAIN)

12 INCHES MIN. (30.5 CM)

LISTED THIMBLE THROUGH COMBUSTIBLE

WALL

EXHAUST VENT TERMINATION TEE

NOTE - MINIMUM HORIZONTAL LENGTH 3 FT. (914MM), UDING CAP FOR TERMINATION. REFER

FLUE TRANSITION (PROVIDED)

12” (30.5 CM) MINIMUM ABOVE ALL HIGHEST SNOWFALL

COMMON VENTING NOT ALLOWED WHEN HORIZONTALLY VENTING THE UNIT / UTILITY HEATER

FLUE TRANSITION (ATTACHED)

FIGURE 4

NOTE - MINIMUM HORIZONTAL LENGTH FT. (1.5M), NOT INCLUDING CAP FOR TERMINATION.

MAXIMUM HORIZONTAL LENGTH AND NUMBER OF ELBOWS REFER TO TABLE 2


F–VENTINGUSINGAMASONRYCHIMNEYThefollowingadditionalrequirementsapplywhenalinedmasonrychimneyisbeingusedtoventthecompactunit/utilityheater.

1. MasonrychimneysusedtoventCategoryIunitsheatersmustbeeithertile-linedorlinedwithalistedmetalliningsystemordedicatedgasvent.Unlinedmasonrychimneysareprohibited.AcategoryIappliancemustneverbeconnectedtoachimneythatisservicingasolidfuelappliance.Ifafireplacechimneyflueisusedtoventthisappliance,thefireplaceopeningmustbepermanentlysealed.

2. Afanassistedunitheatermaybecommonlyventedintoanexistinglinedmasonrychimneyprovided:

• Thechimneyiscurrentlyservingatleastonedraft-hoodequippedappliance.

• Theventconnectorandchimneyaresizedinaccordancewithventingtablesinthe(American)NationalFuelGasCodeANSIZ223.1or(Canada)CSAB149.1NaturalGasandPropaneInstallationCode.

IMPORTANTSingleapplianceventingofafanassistedunitheaterintoatilelinedmasonrychimney(interiororoutsidewall)isprohibited.ThechimneymustfirstbelinedwitheithertypeB-1ventoraninsulatedsinglewallflexibleventliningsystem,sizedinaccordancewithventingtablesinthe(American)NationalFuelGasCodeANSIZ223.1or(Canada)CSAB149.1NaturalGasandPropaneInstallationCode.

3. AtypeB-1ventormasonrychimneylinershallterminateabovetheroofsurfacewithalistedcaporalistedroofassemblyinaccordancewiththetermsoftheirrespectivelistingsandtheventmanufacturer’sinstructions.

4. Donotinstallamanualdamper,barometricdraftregulator,orfluerestrictorbetweentheunitheaterandthechimney.

5. IftypeB-1double-wallventisusedinsideachimney,nootherappliancecanbeventedintothechimney.OuterwalloftypeB-1ventpipemustnotbeexposedtoflueproducts.

6. Insulationfortheflexibleventpipemustbeanencapsulatedfiberglasssleeverecommendedbytheflexibleventpipemanufacturer.

HORIZONTAL VENTING - RESIDENTIAL INSTALLATION UPWARD SLOPEINDUCED DRAFT BLOWER

12 INCHES MIN. (30.5CM)

VENT TERMINATION CAP

LISTED THIMBLE THROUGH COMBUSTION WALL

CATEGORY III VENT ACCORDING TO THESE INSTALLATION INSTRUCTIONS. SLOPED: + 1/4 INCH FOR 1 FOOT RUN MINIMUM.

NOTE - MINIMUM HORIZONTAL LENGTH 5FT. (1.5M), NOT INCLUDING CAP FOR TERMINATION.

MAXIMUM HORIZONTAL LENGTH AND NUMBER OF ELBOWS REFER TO TABLE 2

COMMON VENTING NOT ALLOWED WHEN HORIZONTALLY VENTING THE UNIT / UTILITY HEATER.

FLUE TRANSITION (PROVIDED)

FIGURE 6

7. ThespacebetweenlinerandchimneywallshouldNOTbeinsulatedwithpuffedmicaoranyotherloosegranularinsulatingmaterial.

8. IftypeB-1ventoraninsulatedflexibleventpipecannotbeusedasliners,thechimneymustberebuilttoaccommodateoneofthesemethodsorsomealternateapprovedmethodmustbefoundtoventtheappliance.Wheninspectionrevealsthatanexistingchimneyisnotsafefortheintendedpurpose,itshallberebuilttoconformtonationallyrecognizedstandards,linedorrelinedwithsuitablematerialsorreplacedwithagasventorchimneysuitableforventingunitheaters.Thechimneypassagewaymustbecheckedperiodicallytoensurethatitisclearandfreeofobstructions.

G–REMOVALOFUNITFROMCOMMONVENTIntheeventthatanexistingunitheaterisremovedfromaventingsystemcommonlyrunwithseparategasappliances,theventingsystemislikelytobetoolargetoproperlyventtheremainingattachedappliances.Thefollowingtestshouldbeconductedwhileeachapplianceisinoperationandtheotherappliancesarenotinoperation,yetremainconnectedtothecommonventingsystem.Iftheventingsystemhasbeeninstalledimproperly,thesystemmustbecorrected.

1. Sealanyunusedopeningsinthecommonventingsystem.

2. Visuallyinspecttheventingsystemforpropersizeandhorizontalpitch.Determinethereisnoblockageorrestriction,leakage,corrosion,orotherdeficiencieswhichcouldcauseanunsafecondition.

3. Ifpracticalcloseallbuildingdoorsandwindowsandalldoorsbetweenthespaceinwhichtheappliancesremainingconnectedtothecommonventingsystemarelocatedandotherspacesofthebuilding.Turnonclothesdryersandanyappliancesnotconnectedtothecommonventingsystem.Turnonanyexhaustfans,suchasrangehoodsandbathroomexhausts,sotheywilloperateatmaximumspeed.Donotoperateasummerexhaustfan.Closefireplacedampers.

4. Followthelightinginstructions.Placetheappliancebeinginspectedinoperation.Adjustthermostatsoappliancewilloperatecontinuously.


5. Testforspillageatthedrafthoodreliefopeningafterfiveminutesofmainburneroperation.Usetheflameofamatchorcandle,orsmokefromacigarette,cigar,orpipe.

6. Afterithasbeendeterminedthateachapplianceremainingconnectedtothecommonventingsystemproperlyventswhentestedasoutlinedabove,returndoors,windows,exhaustfans,fireplacedampersandanyothergas-burningappliancetotheirpreviousconditionofuse.

7. Ifimproperventingisobservedduringanyoftheabovetests,thecommonventingsystemmustbecorrected.Thecommonventingsystemshouldbere-sizedtoapproachtheminimumsizeasdeterminedbyusingtheappropriatetables.

N

MANUAL MAIN SHUT-OFF VALVE

(FURNISHED BY INSTALLER)

GAS SUPPLY CONNECTION

GAS FLOW

DRIP LEG

GROUNDED JOINT UNION

LINE VOLTAGE FIELD WIRING

UNIT

BLACK

BLACK

WHITE

WHITE

EQUIPMENT GROUND

BLACK WIRE WITH WHITE TAPE OR WHITE WIRE WITHOUT TAPE

L1

FIGURE 7

GAS SUPPLY TO UNIT HEATER

ISOLATE GAS VALVE

MANUAL MAIN SHUT-OFF VALVE WILL NOT HOLD NORMAL TEST

PRESSURE

CAP

UNIT HEATER

FIGURE 8

FIGURE 9

ELECTRICAL CONNECTIONSNOTE:TheMHUseriesunit/utilityheatersuseadirectsparkignitionsystem.Thereisnopilotnecessaryasthesparklightsthemainburnerasthegasvalveisturnedon.Thedirectsparkignitioncontrolboardemitsradionoiseduringburnerignition.Thelevelofenergymaybeenoughtodisturbalogiccircuitinamicroprocessorcontrolledthermostat.Itisrecommendedthatanisolationrelaybeusedwhenconnectingtheunitheatertoamicroprocessorcontrolledthermostat.Selectcircuitprotectionandwiresizeaccordingtotheunitratingplate.Installaseparatedisconnectswitch(protectedbyeitherfuseorcircuitbreaker)neartheunitsothatpowercanbeturnedoffforservicing.Removeelectricaljunctionboxcoverandconnectwiringthroughknockoutonthejunctionboxlocatedonthesideoftheheater.Refertoheaterwiringdiagramforconnectioninformation.Use18gaugewireorlargerforlinepowerconnections.Makesuretoconnectlinepowertowireslocatedintheexternalelectricaljunctionboxbehindjunctionboxcover.DO NOT CONNECT LINE POWER TO THERMOSTAT TERMINAL STRIP ON OUTSIDE OF HEATER.

Electricallygroundtheunitinaccordancewithlocalcodesorintheabsenceoflocalcodes,inaccordancewiththecurrentNationalElectricalCode(ANSI/NFPANo.70)intheUSA,andinCanadawiththecurrentCanadianElectricalCode,Part1CSAC22.1

NOTE:Un-insulatedgroundwiremustbewrappedinelectricaltapetoavoiddamagetotheelectricalsystem.

Makelinevoltageconnectionsasshowninfigure7.Connectfieldwiringasshownonwiringdiagramonunit.Also,refertotypicaldiagraminthismanual.

Tousetheblowerforaircirculationonly,yourthermostatmusthavea“fanonly”orfanselectionsetting.Incaseyourthermostathasthisoption.anadditionalwireshouldberuntothe“G”terminalonthethermostatconnectionblock.Seewiringschematiconpage13.


Whenconnectinggassupplylines,thelengthofthepipingrunfromthemetertotheheatermustbeconsideredindeterminingthepipesizetoavoidexcessivepressuredrop.Alinepressureof7”WC(178mmWC)fornaturalgasshouldbemaintainedwhensizingthepiping.

Alinepressureof13”WC(330mmWC)shouldbemaintainedforpropane(LP)gas.NOTE: CompoundsusedonthreadedjointsorgaspipingmustberesistanttotheactionsofLiquefiedpetroleumgasses.

WARNING: TO PREVENT HEATER DAMAGE. WHEN USING A PROPANE TANK TO SUPPLY HEATER, AMINIMUM11”W.C.LOWPRESSUREREGULATORTOAMAXIMUM14”W.C.LOWPRESSURE REGULATOR IS REQUIRED. THIS REGULATOR MUST BE INSTALLED BETWEEN THE TANK AND THE HEATER. Regulator not supplied with heater.

Forcorrectsizingofpiping,refertothe(American)NationalFuelGasCodeANSIZ223.1,or(Canada)CSAB149.1,NationalGasandPropaneInstallationCodeorconsulttheutilityhavingjurisdiction.

Adriplegshouldbeinstalledintheverticalpiperuntotheunit.Insomelocalities,codesmayrequirethatamanualmainshutoffvalveandunion(furnishedbyinstaller)beinstalledexternaltotheunit.Unionmustbeofthegroundjointtype.Adriplegshouldbereadilyaccessibletopermitcleaningandempting.Seefigure 8.

NOTE:Leaveaminof4’’clearancetotheelectricalconnectionsboxonthebackoftheheatertoallowforaccess.

A1/8”NPTpluggedtapshallbeinstalledimmediatelyupstreamofthegassupplyconnectiontotheheater.Thepurposeofthisistobeabletocheckforpropergaspressureenteringtheheater.

LEAK CHECKCAUTIONDONOTusematches,candles,flameorothersourcesofignitiontocheckforgasleaks.

Aftergaspipingiscompleted,carefullycheckallpipingconnections,(fieldandfactory),forgasleaks.Useasoapsolutionorotherpreferredmeans.

Duetothenaturalheatingcyclesandvibrationofthisunititisrecommended,aspartofitsannualmaintenance,tochecktheseconnectionsforpropertightnessandleak-checkwithasoapsolutionorotherpreferredmeanspriortoputtingintoservice.

IMPORTANTTheheateranditsindividualshutoffvalvemustbedisconnectedfromthegassupplypipingsystemduringanypressuretestingofthatsystemattestpressuresinexcessof1/2psig(3.45kPa).

Theappliancemustbeisolatedfromthegassupplypipingsystembyclosingitsindividualmanualgasshutoffvalveduringanypressuretestingofthegassupplysystemattestpressuresequaltoorlessthan1/2psig(3.45kPa).Seefigure 9.NOTEIncaseemergencyshutdownisrequired,shutdownmaingasvalveanddisconnectmainpowertounit.Thesedevicesshouldbeproperlylabeledbytheinstaller.

START–UPANDOPERATION

UNITSTART–UPFORYOURSAFETYREADBEFORELIGHTING

BEFORE LIGHTINGsmellallaroundtheapplianceareaforgas.Besuretosmellnexttothefloorbecausesomegasisheavierthanairandwillsettleonthefloor.

Useonlyyourhandtomovethegascontrolknobtotheonposition.Neverusetools.Donotuseexcessiveforcetoswitchvalvefromofftoonposition.Forceorattemptedrepairmayresultinafireorexplosion.

MHU50/80/125unitheatersareequippedwithanautomaticsparkignitionsystem.Thereisnopilot.Incaseofasafetyshutdown,movethermostatswitchtoOFF,thenreturnthethermostatswitchtoHEATposition.

Shouldoverheatingoccur,orthegassupplyfailtoshutoff,shutoffthemanualgasvalvetotheappliancebeforeshuttingofftheelectricalsupply.

GAS VALVE OPERATION FOR HONEYWELL VR8205M SERIES VALVE

1. STOP!Makesureyouhavereadandunderstandallofthesafetyinformationregardingtheoperationofthisgasappliance.Anyandallserviceshouldbeperformedbyalicensedinstaller.

2. Setthethermostattolowestsetting.3. Turnoffallelectricalpowertoappliance.

4. Thisapplianceisequippedwithanignitiondevicewhichautomaticallylightsburner.DO NOTattempttolighttheburnersmanually.

WARNINGElectric shock hazard. Can cause injury or death. Do not use this heater if any part has been under water. Immediately call a qualified service technician to inspect the furnace and to replace any part of the control system and any gas control which has been under water.

Electric shock hazard. Can cause injury or death. Before attempting to perform any service or maintenance, turn the electrical power to unit OFF at disconnect switch(es). Unit may have multiple power supplies.

WARNING

Danger of explosion and fire. Can cause injury or product or property damage. You must follow these instructions exactly.

WARNINGDanger of explosion. Can cause injury or product or property damage. If over-heating occurs or if gas supply fails to shut off, shut off the manual gas valve to the appliance before shutting off electrical supply.

GAS CONNECTION

GAS VALVE ROTARY SWITCH KNOB

MANIFOLDPRESSURE

ADJUSTMENTSCREW UNDER CAP

MANIFOLDPRESSURE TAP

FIGURE 10

WARNING


5. Thereisablackrotaryswitchknobthatcanbemovedbetweentheonandoffposition.Rotatetheswitchknobtotheoffposition.(SeeFigure10)

6. Waitfiveminutestoclearoutanygas.Ifyouthensmellgas,STOP!Immediatelycallyourgassupplierfromaneighbor’sphone.Followthegassupplier’sinstructions.Ifyoudonotsmellgasgotonextstep.

7. RotatetheblackswitchknobtoON.

8. Turnonelectricalpowertounit.

9. Setthethermostattodesiredsetting.

10. Thecombustionairblowerwillstart.Theburnerswilllightwithin30seconds.

11. Ifunitdoesnotlightfirsttime(gaslinenotfullypurged)itwillattemptuptotwomoreignitionsbeforelockingout.

12. Iflockoutoccurs,repeatsteps1through9.

13. Ifappliancestillwillnotoperate,followtheinstructions“TOTURNOFFGASTOUNIT”andcallyourservicetechnicianorgassupplier.

TO TURN OFF GAS TO UNIT1. Setthermostattolowestlevel.

2. Turnoffallelectricalpowertounitifserviceistobeperformed.

3. RotateblackknobtoOFFposition.

HEATING SEQUENCE OF OPERATION

1. Whenthethermostatcallsforheat,thecombustionairblowerstartsimmediately.

2. Combustionairpressureswitchprovesbloweroperationbeforeallowingpowertotheignitioncontroller.Thisswitchisfactorysetandnoadjustmentisnecessary.

3. Afterpre-purgeofapproximately30seconds,thesparkignitionisenergizedandthesolenoidvalveopensinthegasvalve.

4. Thesparkthenignitesthegas,theignitionsensorprovestheflameandthecombustionprocesscontinues.

5. Intheeventthattheflameisnotdetectedafterthefirst10-secondtrialforignition,thecontrollerwillrepeatsteps3and4anadditionaltwotimesbeforelockingoutthegasvalve.Refer to ignition control board table 3.Ignitioncontrolwillthenautomaticallyrepeatsteps3,4,and5after60minutes.

Tointerruptthe60-minutelockoutperiod,movethermostatfrom“HEAT”to“OFF”thenbackto“HEAT.”Heatingsequencethenrestartsatstep1.

6. Theburnersshalllightwithoutnoticeablecrossoverdelay.Thereshallbenoflameliftingfromtheburnerheads,flashbackorburningwithintheburner.Theflamesshallbepredominantlyblueincolorandshallbeapproximatelycenteredinthetubeswithnoapparentimpingementtakingplace.Ifyourburnercharacteristicsdonotmatchthosedescribedabove.Refertothetroubleshootingsections.

7. Theignitioncontrolwillenergizethefanapproximately45secondsafterignitionisestablished.

8. Afterthethermostatdemandissatisfiedthegasvalveisclosed;5secondsafterthedemandissatisfiedthecombustionairblowerisshutoff.

9. Thecontrolcentershallshutoffthesystemfanapproximately150secondsafterthegasvalveisde-energized.

IGNITION CONTROL LEDTheignitioncontrolboardcontainsagreenLEDwhichindicatesthefollowing:

TABLE 3 IGNITION CONTROL LED

LIMIT CONTROLThelimitcontrolswitchisfactorysetandnotfieldadjustable.

LOUVER VANE ADJUSTMENTS

Rotatelouvervanestodirectairflowupward,downward,straight,oranycombinationofthesedirections.Whenunitisinstalledinaninvertedposition,louversmaybepositionedinthesamemanner.

COMBUSTION AIR PRESSURE SWITCH

Thispressureswitchchecksforpropercombustionairbloweroperationbeforeallowinganignitiontrial.Theswitchisfactorysetandnofieldadjustmentisnecessary.Ifa3flashLEDoccursPleasemakesureyourventingisnotblockedup.Next,removetheendofthepressureswitchtubingfromtheEXHAUSTFANhosebarb.Theremightbeanobstructioninthehosebarbopeningclearouttheopeningwithathinobjectthatwillfitinsidethehosebarb.PushthatthroughthelengthofthehosebarbPLUSatleastanother1/2inch,intotheexhaustfanhousing.Thiswillclearoutanythingstoppingthevacuumfromengagingthepressureswitch.

FLAME ROLLOUT SWITCHTheflamerolloutswitch(es)arelocatedontheburnerboxtop,behindtheignitioncontrolboard.Thisnormallyclosedswitchopensonatemperaturerise.Checkforadequatecombustionairbeforemanuallyresettingswitch.

HIGH ALTITUDEUnitsmaybefiredatfullinputupto2000ft.(610m)abovesealevel.Above2000ft.(610m),manifoldpressuremustbeadjustedonsomeunits.Adjustpressureregulatortopressureshownintable 4fornaturalgasandtable 5forLP/propanegas.

LED UNIT OPERATION

SlowFlash* NormalOperation-Nocallforheat

FastFlash NormalOperation-Callforheat

CurrentsignalatFLAMEterminal0.6to1.0microamps

2Flashes Systemlockout-failedtodetectorsustainflame

CurrentsignalatFLAMEterminal<0.6microamps

3Flashes PressureswitchfailedclosedbeforeCABisenergized

orfailedopenafterCABisenergized

4Flashes Highlimitorrolloutswitchopen

5Flashes Flamesensedandgasvalvenotenergized

SteadyOff Lossofpower/Check3AMPFuseoncircuitboard

SteadyOn Ignitioncontrolfailure

*WhenthermostatisplacedincontinuousfanmodeLEDwillslowlyflash.


GAS FLOWTocheckforpropergasflowtothecombustionchamber,determinetheBtuinputfromtheapplianceratingplate.DividethisinputratingbytheBtupercubicfeetofavailablegas.Resultistherequirednumberofcubicfeetperhour.Determinetheflowofgasthroughthegasmeterfortwominutesandmultiplyby30togetthehourlyflowofgas.

GAS PRESSURE1. Checkgaslinepressurewithunitfiringatmaximumrate.A

minimumof5.0”w.c.fornaturalgasor10.9”w.c.forLP/propanegasshouldbemaintainedforproperunitoperation.

2. Afterlinepressurehasbeencheckedandadjusted,checkmanifoldpressure.Correctmanifoldpressureisshownontheunitratingplate.Seefigure 10 forgaspressureadjustmentscrewlocation.AnaturalgastoLP/propanegaschangeoverkitisrequiredtoconvertunit.Refertoinstallationinstructionsprovidedwithchangeoverkitforconversionprocedure.

SERVICECAUTIONTurnoffgasandelectricalpowertounitbeforeperforminganymaintenanceorserviceoperationsonthisunit.Remembertofollowlightinginstructionswhenputtingunitbackintooperationafterserviceormaintenance.

Ifanyoftheoriginalwireassuppliedwiththeappliancemustbereplaced,itmustbereplacedwithwiringmaterialhavingatemperatureratingofatleast105°C.Donotusethisapplianceifanyparthasbeenunderwater.Immediatelycallaqualifiedservicetechniciantoinspecttheapplianceandreplaceanygascontrolwhichhasbeenunderwater.

BURNERS1. Periodicallyexamineburnerflamesforproperappearance

duringtheheatingseason.

2. Beforeeachheatingseasonexaminetheburnersforanydepositsorblockagethatmayhaveoccurred.

3. Cleanburnersasfollows:• Turnoffbothelectricalandgassuppliestounit.

• Disconnectgassupplypiping,hightensionandsensorleads.Removegasmanifold.Removeburnertray.

• Cleanburnersasnecessary.Makesurethatburnerheadslineupproperlytoensureflamecrossover.Checksparkgaponelectrodeandadjustifrequired.Thegapshouldbebetween0.110inchand0.140inch(2.79mm

to3.56mm).Thegapmaybecheckedwithappropriatelysizedtwistdrillsorfeelergauges.

• Reinstallburnertray,gasmanifold,hightensionandsensorleads.Reconnectgassupplypiping.

• Restoreelectricalpowerandgassupply.Followlightinginstructionstolightunit.Checkburnerflame.

FLUE PASSAGEWAY AND FLUE BOXThefluepassagesandflueboxshouldbeinspectedandcleanedpriortoeachheatingseason.Thesequenceofoperationshouldbeasfollows:

1. Turnoffbothelectricalandgassupplytounit.

2. Disconnectcombustionairblowerwiring.

3. Removescrewssecuringflueboxtounit.Removefluebox.Ifnecessary,removeblowerassemblyfromfluebox.Cleanflueboxwithwirebrush.

4. Removeturbulatorretentionbracketandturbulators.Cleanturbulatorswithwirebrush.

5. Removeburnersasdescribedinsection“BURNERS”section.

6. Cleantubeswithawirebrush.

7. Reassembleunit.Thecombustionairandflueboxgasketsshouldalsobereplacedduringreassembly.

8. Restoreelectricalpowerandgassupply.Followlightinginstructionstolightunit.Checkoperationofunit.

COMBUSTION AIR BLOWERUndernormaloperatingconditions,thecombustionairblowershouldbecheckedandcleanedpriortotheheatingseasonwiththepowersupplydisconnected.Useasmallbrushtocleanblowerwheel.

ELECTRICAL1. Checkallwiringforlooseconnections.

2. Checkforcorrectvoltageatunit(unitoperating).

3. Checkamperagedraw.

FLUE AND CHIMNEYCheckallventandventconnectorjointsfortightness.Ensurethatconnectionsaresealedandthattherearenoblockages.

FAILURE TO OPERATEIfunitfailstooperatecheckthefollowing:

1. Isthermostatcallingforheat?

2. Ismaindisconnectclosed?

3. Isthereabreakertrippedorafuseblown?

4. Isgasturnedonatmeter?

5. Ismanualshutoffvalveopen?

6. Isunitignitionsysteminlockout?Ifunitlocksoutagain,callservicetechniciantoinspectunit.

7. Ispressureswitchclosed?Obstructedfluewillcauseunittoshutoffatpressureswitch.Checkfluepassageandoutlet.

Table4NATURALGASMANIFOLDPRESSURES-IN.W.C..(KPA)

MHU50/80/125ALTITUDEFT.(M)

0-2000(0-610)

2000-4500(610-1370)

50/80/125 4.0”WC(0.99KPA)* 3.6”WC(0.89KPA)

*NOADJUSTMENTREQUIRED

Table5LP/PROPANEGASMANIFOLDPRESSURES-IN.W.C..(KPA)


0-2000(0-610)

2000-4500(610-1370)

50/80/125 10”WC(2.62KPA)* 8.5”WC(2.12KPA)



LADDER DIAGRAM

ITISRECOMMENDEDTOUSE

OPTIONAL THERMOSTAT INSTALLATION

18AWGWIREWHENINSTALLINGTHETHERMOSTAT.CONNECT

TERMINALS‘R’AND‘W’THERMOSTATWIRINGTO

ASILLUSTRATEDONTHESCHEMATICDIAGRAM.

o É Ç

t Ü á íÉ

NOTE:THERMOSTATTERMINALCONNECTIONSAREMOUNTEDONTHEBACKPANELOFTHEHEATER.

EXTERNALTHERMOSTATTERMINALSTRIPWARNING:DO NOT CONNECTLINEPOWERTOTHETHERMOSTATTERMINALSTRIP.

Red

White


HONEYWELLKIT#393691

Section 1 FUEL CONVERSION KITS

For L.P. - to - Natural Gas Conversions

FUEL CONVERSION INSTRUCTIONS

FuelConversionPartNumbers

Model# BTU/HR

Natural-To-LPF260163

MHU50 50,000

MHU80 80,000

MHU125 125,000

FuelConversionPartNumbers

Model# BTU/HR

Natural-To-LPF260164

MHU50 50,000

MHU80 80,000

MHU125 125,000

For Natural - to L.P. Gas Conversions

PartNumber Description 50 80 125

13575 Gasconversionlabel 1 1 1

60166-10 Ratingtag 1


11727 Spring-gasvalve(labelinc.) 1 1 1

60156 L.P.Orifice 3 5 8

13576 ControlConversionLabel 1 1 1

GasConversionLabels

OrificeP/N(SeeTableBelow)

HONEYWELLKIT#393691

GasConversionLabels

OrificeP/N(SeeTableBelow)

PartNumber Description 50 80 125

13575 Gasconversionlabel 1 1 1



11727 Spring-gasvalve(labelinc.) 1 1 1

60049 L.P.Orifice 3 5 8

13576 ControlConversionLabel 1 1 1


Section 2 FUEL CONVERSION INSTRUCTIONSFigure1

WARNING: Explosion Hazard Turnoffthegassupplytotheheater beforeperforminganyserviceor maintenance.

Failuretofollowtheseinstructionswill resultindeath,injuryorpropertydamage.

WARNING: Electrical Shock Hazard Unplugtheelectricalcordfromtheoutlet beforeperforminganyservice maintenance.

Failuretofollowtheseinstructionswill resultindeath,injuryorpropertydamage.

Step 1

CAUTION THE UNIT MUST NOT BE CONNECTED TO EITHER THE GAS SUPPLY OR THE ELECTRICAL POWER SUPPLY, BEFORE PROCEEDING WITH CONVERSION.

Step 2Removeandretainthefourscrewsholdingthemanifoldontotheburnerbox(Figure1).Rotatethevalve/manifoldassembly,awayfromtheburners(Figure2).Thevalve/manifoldassemblyholdstheorifices(3-MHU50,5-MHU80,8-MHU125).Thiswillallowaccesstotheorificesonthemanifold,andalsotheadjustmentspringinthevalve/regulator.

Step 3Removeanddiscardtheadjustmentspringcapfromgasvalve/regulatorwithaflatbladescrewdriverbyturningthescrewcounter-clockwise.Removeanddiscardtheregulatoradjustmentscrewfoundunderthecap.Removeanddiscardthespringthatislocatedundertheadjustmentscrew.Takethespringkitfromtheconversionkit,andcomparethepartnumberofthekittothepartslistonpage3.Ifitdoesnotmatch,immediatelycontactMr.Heater,Inc.forthecorrectkit.Afterconfirmingthespringkitiscorrectfortheheatermodelyouareconverting,installthenewspringandadjustmentscrew.Turnspringadjustmentscrewclockwise(in)untilthescrewstops,thenturnitcounter-clockwise(back)1½turns.Placeconversionlabelsuppliedwiththespringkitonthevalveneartheadjustmentscrewcoveropening.

Step 4Removeanddiscardtheorifices(3-MHU50,5-MHU80,8-MHU125)fromthemanifoldwithusinga½“openendwrench.Turnthemcounter-clockwisetoremove.Taketheneworificesfromtheconversionkitandbeforeinstalling,confirmthatthenumberstampedonthesideoftheorificematchesthenumberforthekitbeinginstalled.Ifitdoesnot,immediatelycontactMr.Heater,Inc.forthecorrectkit.Iftheyarethecorrectorifices,installtheminthemanifoldusingcautionnottocrossthread.

The electrode and sensor are not adjustable. DO NOT change location or position as part of this conversion kit.

4Screws

RotateValve/ManifoldAssembly


Figure2

N.G. L.P.

6

5

4

3

2

1

0

1

2

3

4

5

6

6

5

4

3

2

1

0

1

2

3

4

5

6

4" 10"

Step 5Rotatethevalve/manifoldassemblybackupintotheburnerbox,makingsurethatalltheorificesareindexedintotheburnersandarenotcaughtonthelocatingringonthebackofeachburner.Securethemanifoldtotheburnerboxwiththefourscrewsremovedinstep2.

Step 6Followingtheinstructionsintheunitheatersoperationsmanualmounttheheaterandconnectthegassupply(makingsuretoleakcheckallconnectionswithsoapywater).

Step 7Removevalvepressuretestplugandretainforlateruse.Connectawater-filledU-tubemanometertothetestport.SeeFigure2.Useamanometerbecausetestgaugesarenotreliableandmaygiveafalsereading.

Step 8Connectmainelectricalpowersupply,andturnmaingassupplyon.

Step 9Turnupthethermostattocallforheat,therebystartingtheignitionsequencefortheheater.

Step 10

Whentheburnerslight,setthemanifoldgaspressurebyturningtheadjustmentscrewtotheregulatorspringthatwasreplacedinstep6.Oncethehasbeenadjusted,replacetheadjustmentscrewcoverwithanewonefromtheconversionkit.

TheNaturalGasunitshouldbesetto4”WCandtheLPunitshouldbesetto10”WC.Themanometerillustration(SeeFigure2)showseachofthepressurereadings.

Step 11

Turndownthethermostatandallowtheheatertocompleteacooldowncycle.Thendisconnectmainelectricalpower,andturnthemaingassupplyofftoappliance.

Step 12

Disconnectthemanometerfromapplianceandreplacethetestplugonvalveremovedinstep6.


Section 3 RATING TAG CONVERSION

Figure3

Figure4

INLET PRESSURES:

Natural Gas

MAX-14"WC(3.49kPa)

MIN-5"WC(1.25kPa)

Propane

MAX-14"WC(3.49kPa)

MIN-10"WC(2.74kPa)

Step 13

Connectmainelectricalpower,andturnmaingassupplybackon.Turnupthermostattocallforheat.Whenthemainburnerslightusingsoapywatercheckallconnectionsthoroughlyforgasleaks.Rememberingtoalsocheckthepressuretestplugreplacedinstep12.Allowtheheatertooperateforatleast5minutes,thenobservethemainburnerflame.Ahardblueflameextendingintothetubeisnormal.Slightyellowtippingisacceptable.Thereisnoairadjustmenttotheburner.

Step 14

Seefigure3.Removethedatatagfortheirrespectivegases.Removelabelandplaceovertheexistingportionofthetag.Thistagispreprintedwithallthecorrectinformationfortheconvertedheater.

Step 15

Removetheconvertedinformationtagfromthekitandfillintheinformation.Thenplacethistagbelowtheupdatedratingtagontheunit.

Step 16

Replaceanypanelsandoperateheaterfollowingallwarnings/cautionsandinstructionsintheoperator’smanualandlabels.

Table4NATURALGASMANIFOLDPRESSURES-IN.W.C..(KPA)


0-2000(0-610)

2000-4500(610-1370)

50/80/125 4.0”WC(0.99KPA)* 3.6”WC(0.89KPA)


TABLE5LP/PROPANEGASMANIFOLDPRESSURES-IN.W.C..(KPA)


0-2000(0-610)

2000-4500(610-1370)

50/80/125 10”WC(2.62KPA)* 8.5”WC(2.12KPA)


Figure5&Figure6


P U

P R

P V

Q M

36

38

37

35

MrHeater•Compact/UtilityHeater•Model#MHU50/80

REPAIR PARTSWhenorderingpartsincludethecompleteunitmodelnumberlistedontheunitratingplate.


PARTS LIST:SEE BACK PAGE FOR PARTS ORDERING INFORMATION

Optional Installation Components 24VTHERMOSTAT..................................................................................F210359 4”VERTICALVENTKIT(50/80/125)........................................................F102848 4”HORIZONTALSTAINLESSSTEELVENTKIT(50/80/125).......................F102860

Gas Conversion Kits Natural Gas to Liquid Propane MHU50/80/125 .........................................................................F260163 Liquid Propane to Natural Gas MHU50/80/125 .........................................................................F260164

REF# Description 50K QTY 80K QTY

1 CIRCUITBOARD 60105 1 60105 1

2 LIMITSENSOR 60022 1 60021 1

3 ELECTRODEIGNITER 60139 1 60139 1

4 ELECTRODESENSOR 60141 1 60141 1

5 BURNER 60155 3 60191 5

6 IGNITIONLEAD 60045 1 60045 1

7 SENSORLEAD 60046 1 60046 1

8 ORIFICE(NAT) 60049 3 60049 5

9 ORIFICE(LP) 60156 3 60156 5

10 GASVALVE(NAT) 60128 1 60128 1

11 GASVALVE(LP) 60129 1 60129 1

12 TRANSFORMER 60025 1 60025 1

13 PRESSURESWITCH 60147 1 60146 1

14 HIGHLIMITSENSORHEATEXCH. 60015 1 60015 1

15 PRESSURESWITCHTUBE 60031 1 60031 1

16 INDUCEDDRAFTMOTOR 60020 1 60020 1

17 VENTADAPTER 60130 1 60140 1

18 INDUCEDDRAFTMOTORGASKET 60157 1 60157 1

19 BACKBRACKET 60075 1 60075 1

20 FRONTBRACKET 60080 1 60080 1

21 LOUVERS 60100 5 60100 7

22 LOUVERSPRING 60103 5 60103 7

23 FLUEBOX 60189 1 60190 1

24 FLUEBOXGASKET 60090 1 60092 1

25 HEATEXCHANGER 60065 1 60068 1

26 ACCESSDOOR 60070 1 60072 1

27 FRONT 60095 1 60097 1

28 SIDEDOOR 60110 1 60112 1

29 WRAPPER 60115 3 60117 3

30 FANMOTOR 60055 1 60054 1

31 FANGUARD 60120 1 60122 1

32 FANASSEMBLY 60125 1 60127 1

32 CAPACITORSTARTER 1 28788 1

34 MANIFOLD 60062 1 60064 1

35 INLETPIPE 60132 1 60132 1

36 THERMOSTATTERMINAL 60144 1 60144 1

37 WIRINGJUNCTIONBOX 60159 1 60159 1

38 COVER,JUNCTIONBOX 60160 1 60160 1

39 GASVALVEBRACKET 60158 1 60158 1


MrHeater•Compact/UtilityHeater•Model#MHU125

42

4

7

25

21

8

2

315

5

6

45

32

9 10 11

12

14

13

16

23

18

39

24

22

40

19

25

28

27

26

30

35

31

1744

43

37

1

3433

41

29

20

36

38

44


REF# Description 125 QTY

1 BRACKET 60200 2

2 MOUNTINGPANEL,MOTOR 60201 1

3 MOUNTINGPANEL,FRONTANDBACK 60202 2

4 MOUNTINGPANEL,BOTTOM 60203 1

5 MOUNTINGPANEL,SIDE 60204 1

6 MOUNTINGPANEL,TOP 60205 1

7 HEATEXCHANGER 60206 1

8 BRACKET,HEATEXCHANGE 60207 2

9 FANMOTOR 60208 1

10 FANGUARD 60209 1

11 FANASSEMBLY 60210 1

12 LOUVERS 60211 8

13 LOUVERSSPRING 60212 8

14 COVER,WIRINGJUNCTIONBOX 60160 1

15 WIRINGJUNCTIONBOX 60159 1

16 THERMOSTATTERMINAL 60144 1

17 VENTADAPTER 60213 1

18 INDUCEDDRAFTMOTOR 60214 1

19 INDUCEDDRAFTMOTORGASKET 60215 1

20 FLUEBOX 60216 1

21 FLUEBOXGASKET 60217 1

22 PRESSURESWITCHTUBE 60218 1

23 PRESSURESWITCH 60219 1

24 HILIMITSENSORHEATEXCH 60220 1

25 LIMITSENSOR 60221 2

26 CAP,FANMOTOR 28735 1

27 CAP,INDUCEDDRAFTMOTOR 60222 1

28 TRANSFORMER 60025 1

29 CIRCUITBOARD 60105 1

30 BRACKET,CAP 60223 1

31 SENSORLEAD 60046 1

32 ELECTRODESENSOR 60141 1

33 IGNITERLEAD 60224 1

34 ELECTRODEIGNITER 60139 1

35 BURNER 60155 8

36 BURNERBOX 60225 1

37 BRACKETBURNER 60226 1

38 ORIFICE(NAT) 60049 8

39 ORIFICE(LP) 60156 8

40 MANIFOLD 60227 1

41 GASVALVE(NAT) 60128 1

42 INLETPIPE 60132 1

43 GASVALVEBRACKET 60158 1

44 PANEL,BURNBOX 60228 1

*** INSULATIONPADDING 60220 1

PARTS LIST:SEE BACK PAGE FOR PARTS ORDERING INFORMATION


WARNING:USEONLYMANUFACTURER’SREPLACEMENTPARTS.USEOFANYOTHERPARTSCOULDCAUSEINJURYORDEATH.REPLACEMENTPARTSAREONLYAVAILABLEDIRECTFROMTHEFACTORYANDMUSTBEINSTALLEDBYAQUALIFIEDSERVICEAGENCY.

PARTS ORDERING INFORMATION:PURCHASING: AccessoriesmaybepurchasedatanyMr.HeaterlocaldealerordirectfromthefactoryFOR INFORMATION REGARDING SERVICEPleasecallToll-Free800-251-0001•www.mrheater.comOurofficehoursare8:00AM–5:00PM,EST,MondaythroughFriday.Pleaseincludethemodelnumber,dateofpurchase,anddescriptionofprobleminallcommunication.

LIMITED WARRANTYThecompanywarrantsthisproducttobefreefromimperfectionsinmaterialorworkmanship,undernormalandproperuseinaccordancewithinstructionsofTheCompany,foraperiodofthreeyearsonparts(limited)and10yearsontheheatexchanger,fromthedateofdeliverytothebuyer.TheCompany,atitsoption,willrepairorreplaceproductsreturnedbythebuyertothefactory,transportationprepaidwithinsaidoneyearperiodandfoundbytheCompanytohaveimperfectionsinmaterialorworkmanship.

Ifapartisdamagedormissing,callourTechnicalSupportDepartmentat800-251-0001.

AddressanyWarrantyClaimstotheServiceDepartment,Mr.Heater,Inc.,4560W.160THST.,CLEVELAND,OHIO44135.Includeyourname,addressandtelephonenumberandincludedetailsconcerningtheclaim.Also,supplyuswiththepurchasedateandthenameandaddressofthedealerfromwhomyoupurchasedourproduct.

TheforegoingisthefullextentoftheresponsibilityoftheCompany.Therearenootherwarranties,expressorimplied.Specificallythereisnowarrantyoffitnessforaparticularpurposeandthereisnowarrantyofmerchantability.InnoeventshalltheCompanybeliablefordelaycausedbyimperfections,forconsequentialdamages,orforanychargesoftheexpenseofanynatureincurredwithoutitswrittenconsent.Thecostofrepairorreplacementshallbetheexclusiveremedyforanybreachofwarranty.Thereisnowarrantyagainstinfringementofthelikeandnoimpliedwarrantyarisingfromcourseofdealingorusageoftrade.Thiswarrantywillnotapplytoanyproductwhichhasbeenrepairedoralteredoutsideofthefactoryinanyrespectwhichinourjudgmentaffectsitsconditionoroperation.

Somestatesdonotallowtheexclusionorlimitationofincidentalorconsequentialdamages,sotheabovelimitationorexclusionmaynotapplytoyou.ThisWarrantygivesyouspecificlegalrights,andyoumayhaveotherrightswhichvaryfromstatetostate.

Mr.Heater,INC.,4560W.160THST.,CLEVELAND,OHIO44135•1-800-251-0001Mr.HeaterisaregisteredtrademarksofMr.Heater,Inc.©2016,Mr.Heater.Allrightsreserved

Mr.Heater,Inc.reservestherighttomakechangesatanytime,withoutnoticeorobligation,incolors,specifications,accessories,materialsandmodels.

OPERATING INSTRUCTIONS ANDOWNER’SMANUAL

READ INSTRUCTIONS CAREFULLY:Readandfollowallinstructions.Placeinstructionsinasafeplaceforfuturereference.Donotallowanyonewhohasnotreadtheseinstructionstoassemble,light,adjustoroperatetheheater.

MHU50MHU80MHU125

Model#

PRODUCTREGISTRATION:Thankyouforyourpurchase.Pleaselogintohttp://www.egiregistration.comtoregisteryourproduct.

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Model # COMPACT UNIT HEATER