Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 13-90-30004671

Nous recommandons que nos appareils de chauffage au bois soient installés et entretenus apr des professionnels qui ont été accrédités aux É.-U. par le National Fireplace Institute® (NFI) comme étant des spécialistes du NFI en matière d’appareilsde chauffage au ois, ou qui sont accrédités au Canadadans le cadre du Programme de formation techniqueen énergie du bois (WETT)

4671Merrimack cover

For Use in North America

Merrimack Large Wood Insert

Owner’s ManualOperation & Care

INSTALLER: Leave this manual with party responsible for use and operation. OWNER: Retain this manual for future reference. Contact your dealer with questions on installation, operation, or service.

If the information in these instructions is not followed exactly, a fire may result causing property damage, personal injury, or death.

WARNING!

• Donotstoreorusegasolineorotherflammablevaporsand liquids in the vicinity of this or any other appliance.

• Donotoverfire - Ifapplianceorchimneyconnectorglows, youare over firing.Over firingwill void yourwarranty.

• Complywithallminimumclearancestocombustiblesasspecified.Failuretocomplymaycausehousefire.

HOT SURFACES!Glass and other surfaces are hot during operation AND cool down. Hot glass will cause burns.

WARNING!

• Do not touch glass until it is cooled• NEVER allow children to touch glass• Keep children away• CAREFULLYSUPERVISEchildreninsameroomas

fireplace.• Alert children and adults to hazards of high

temperatures• High temperatures may ignite clothing or other

flammable materials.• Keep clothing, furniture, draperies and other

flammablematerialsaway.

NOTETo obtain a French translation of thismanual, pleasecontact your dealer or visit www.vermontcastings.comPourobtenirunetraductionfrançaisedecemanuel,s’ilvous plaît contacter votre revendeur ou visitez www.vermontcastings.com

Installationandserviceofthisapplianceshouldbeperformedbyqualifiedpersonnel.Hearth&HomeTechnologiesrecommendsHHTFactoryTrainedorNFIcertifiedprofessionals.

This unit has been retired.Service parts pages within have

been removed.For replacement parts, please

refer to the individual service parts list located on the brand website.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 23-90-30004671

Introduction

Save These Instructions for Future Reference

The Merrimack Large Insert is designed, tested and listed for burning wood. Do not burn other fuels.The Merrimack Large Insert is not listed for mobile home installations.Failure to follow these instructions may result in property damage, bodily injury or even death.

Specifications .........................................................3

Dimensions .............................................................4

Installation ..............................................................5

Smoke Alarm/Safety Tip .........................................9

Operation ..............................................................10

Maintenance .........................................................12

OptionalAccessories ............................................17

Warranty ...............................................................18

Table of Contents

Proposition 65 Warning:Fuelsusedingas,woodburningoroilfiredappliances,and theproductsofcombustionof such fuels, contain chemicals known to the State ofCalifornia to cause cancer, birth defects and otherreproductive harm.CaliforniaHealth&SafetyCodeSec.25249.6

ThankyouforpurchasingaVermontCastingsMerrimackLargeInsert,anefficientwoodstovecarefullyengineeredtobringyouthelatestinwoodcombustionprinciplesandmodernfoundrytechnology.Thisstovetransformsatraditionalmasonryfireplaceintoapowerfulheater.Youcancountonyearsofcomfortableheatingandpleasurablefire-viewingifyouoperateandmaintainitaccordingtothedirectionsinthisOwner'sGuide.This Inserthasbeentestedand listedbyOMNI-TestLaboratoriesofPortland,OregontoUL1482-1996(R2006) for theUnitedStatesandULCS628-93forCanada.ThisInsertislistedto,andincompliancewith,thestandardssetforthbytheFederalEnvironmentalProtectionAgency,40CFRPart60.532(b),asstatedonthepermanentlabelattachedtothestove.ThismanualdescribestheinstallationandoperationofthisInsert.ThisheatermeetstheU.S.EnvironmentalProtectionAgency'semissionlimitsforwoodheaterssoldafterMay15,2015.Underspecifictestconditionsthisheaterhasbeenshownto deliver heat at a rate ranging from 10,750 to 31,780 BTU/hr.Formorecompletedetailsonstoveperformanceandspecifications,pleaserefertoPage3.TheMerrimackLargeInsertisdesigned,testedandlistedforburningwood.Donotburnotherfuels.InstallationorserviceoftheMerrimackLargeInsertshouldbeperformedonlybyaqualifiedinstaller,preferablyNFIorWETT(Canada)certified.PleasereadentiremanualbeforeyouinstallanduseyournewInsert.Failuretofollowtheseinstructionsmayresultinpropertydamage,bodilyinjuryorevendeath.

WARNING!This stove has not been tested with an unvented gas log set. To reduce the risk of fire or injury, do not install an unvented gas log set into this fireplace.

= Contains updated information

! WARNINGThis product and the fuels used to operate this product (wood),andtheproductsofcombustionofsuchfuels,canexpose you to chemicals including carbon black,whichis known to the State of California to cause cancer, and carbonmonoxide,whichisknowtotheStateofCaliforniato cause birth defects or other reproductive harm. Formoreinformationgoto:www.P65Warnings.ca.gov

California safety information

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/203 3-90-30004671

Specifications

*Weighted average LHV (Low Heating Value) efficiency using Douglas Fir dimensional lumber and data collected during EPA emission test.**Weighted average HHV (High Heating Value) efficiency using Douglas Fir dimensional lumber and data collected during EPA emission test.***A range of BTU outputs based on EPA Default Efficiency and the burn rates from the low and high EPA tests, using Douglas Fir dimensional lumber.****A peak BTU out of the appliance calculated using the maximum first hour burn rate from the High EPA Test and the BTU content of cord wood (8600) times the efficiency.This wood heater needs periodic inspection and repair for properoperation.Itisagainstfederalregulationstooperatethis wood heater in a manner inconsistent with operating instructions in this manual.

MODEL: MerrimackLargeInsertLABORATORY: OMNITestLaboratories,IncREPORT NO. 227-S-37-6.2TYPE: SolidFuelRoomHeater/Wood

Burning TypeSTANDARD(s): UL1482-1996(R2006),

ULC-S628-93(A1997)ELECTRICAL RATING: 115VAC,60Hz

Area Heated................................1,400-2,800SquarefeetLoading ....................................................................... FrontChimney Connector: ......................................6"(152mm)Flue Exit Position .........................................................Top Primary Air ...................................................... Manually SetGlass Panels ...........................High-TemperatureCeramicWeight ......................................................480lbs.(218kg.)Blower Rating .................................150cfm.(115V,60Hz)Power Cord Lenght .....................6FootUseableInstalled

EPA Certification Number: 770EPA Certified Emissions: 3.6g/hr*LHV Tested Efficiency: 73.0%**HHV tested Efficiency: 66.8%***EPA BTU Output: 10,600-31,800****Peak BTU/Hour Output: 55,800Other Important InformationVent Size: 6Inch(152mm)Firebox Size: 3.1 cu. ft.Max. Wood Length: 22"Ideal Wood Length: 20”Fuel Seasoned Cordwood

(20%moisture)

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/204 3-90-30004671

Figure 1-MerrimackLargeInsertdimensions.

29¹⁄₈” (740 mm)

24³⁄₄” (629 mm)

12⁵⁄₁₆”(313 mm)

26⁵⁄₁₆”(668 mm)

17¹¹⁄₁₆” (449 mm)

23¹³⁄₁₆”(605 mm)

4671Merrimack dims

7³⁄₁₆”(183 mm)

31¹⁄₂" (800 mm) 25³⁄₈” (645 mm)

Dimensions

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 53-90-30004671

SAFETY NOTICE: IF YOUR MERRIMACK IS NOT PROPERLY INSTALLED, A HOUSE FIRE MAY RESULT. TO REDUCE THE RISK OF FIRE, FOLLOW THE INSTALLATION INSTRUCTIONS. CONTACT LOCAL BUILDING OR FIRE OFFICIALS ABOUT RESTRICTIONS AND INSTALLATION INSPECTION REQUIREMENTS IN YOUR AREA.Requirements for Existing FireplacesTheMerrimackLargeInsertislistedforinstallationwithinaproperlybuiltmasonryfireplace.Thefireplaceandchimneymustbecleanandstructurallysound.Have them inspected by a qualified professionalchimney sweep, amason, or your Vermont Castings'AuthorizedDealer before theMerrimack Large Insert isinstalled.Anydeterioration (cracks, loosemortaror loosebricks)mustberepaired.Codes may permit removal of the damper in order to make a positive vent connection between the firebox and thechimney.However,thefireplaceshouldnotbemodifiedinanywaywithoutfirstcheckingwithyourlocalbuildinginspectororfiremarshal.Provisionshouldbemadetorestorethefireplaceto its original condition if the insert is removed. Do not remove bricksormortarthatmayjeopardizethecomplianceofthefireplacewithlocalbuildingcodes.The Merrimack Large Insert is not approved for installation in factory-built fireplaces. Requirements for Existing ChimneysChimney requirements differ for the U.S. and Canada.Specificationsforeacharelistedbelow.Connecttheinsertto the chimney in accordance with local codes and the requirementsofthelistingagencyasspecifiedinthismanual.Chimney Height / U.S. and CanadaChimneyheightshouldbenolessthan15'(4.5m)abovethehearthandnomorethan35'(10.5m).Thechimneyshouldextendatleast3'(914mm)abovethehighestpointwhereitpassesthrougharoof,andatleast2'(610mm)higherthananyportionofabuildingwithin10'(3m).(Figure2)DO NOT CONNECT YOUR MERRIMACK LARGE INSERT TO A CHIMNEY FLUE SERVING ANOTHER APPLIANCE.

Installation

In the U.S. (ANSI/NFPA 211, 1988), when installed in a masonry fireplace:

• Aconnectormustextendfromthefluecollartotheflueliner.

• Thecrosssectionalareaofthefluemustbelessthanorequaltothreetimestheareaofthefluec o l l a r . I flarger,thechimneymustbere-lined.

• Meansmustbeprovidedtopreventroomairpassingto the chimney cavity.

• Provisionmustbemadeforremovaloftheinserttocleanthechimneyflue.

General Considerations / U.S.• Whilenot required inmost jurisdictions in theU.S.,

Vermont Castings Group strongly recommends that afullstainlesssteelchimneylinerbeinstalledfortheinsert to the chimney top to increase overall performance and to ease and reduce yearly maintenance.

• Amasonrychimneymustbewell-constructedandmustmeetminimumcoderequirements.Thechimneyflueshould have a code-approvedlinermadeofmasonryorpre-castrefractory tiles,straightorflexiblestainlesssteelpipe,orapoured-in-placeliner.Anunlinedchimneymustberelinedprofessionally.

• Thechimneymusthaveanominalfluesizeof6"(152mm)diameteror28squareinches(181cm2)butnogreaterthan3timeslargeror85squareinches(548cm2).Achimneylargerthanthismustbere-lined.

2' Min.

2' Min.

3'Min.

0 To 10'

3'Min.

0 To 10'

AC617RLTSKC8

2/11/98

Reference Point

Figure 2-The2'-3'-10'ruleforchimneys.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/206 3-90-30004671

Fireplace MinimumsA Width at Face 29-3/4”(756mm)B WidthatDimension‘C’ 25”(635mm)C Depth1 18-1/2”(470mm)D HeightatFace 24-1/4”(616mm)E HeightatDimension‘C’ 24-1/4”(616mm)

Fireplace MaximumsH Lintel Depth 9”(229mm)I Width2 45”(1143mm)J Height2 32”(813mm)1. Theminimumdepthmustbemaintainedfromthefloorofthefireplace

toaheightof21-1/2”(540mm)

2. ThoughtheMerrimackLargeInsertwillfitintolargerfireplaces,thedecorative optional Vermont Castings Group Surround Panels will notcompletelycoverthefireplaceopeningifthesedimensionsareexceeded.Custommadetrimpiecesmaybeused.

A,I

B C

D,JE

D,J

H

C E

FP1084winterwarmfireplace minimum dimensions3/01

Figure 3-UsethesemeasurementstoconfirmthattheMerrimackLargeInsertwillfitintoyourmasonryfireplace.

Minimum Fireplace DimensionsTheMerrimackLargeInsertwillfitmanyfireplaces.Toconfirmthatitwillfityours,measurethelinteldepth,plustheheight,width,anddepthofyourfireplaceandhearth.Comparethemtothemeasurementsintheaccompanyingchart.Ifyouchoosetoinstallanewhearthoveranexistingfireplacehearth,besure to take its thickness into consideration when measuring bothfrontandbackheightofthefireplaceandclearancestoany existing trims and mantels.NOTE: TheclearancebetweentheMerrimackLargeInsertandthemantel,toptrimandsidetrimcannotbereducedbyinstalling shields.Anotherrequirementtoconsideristheclearanceformovableitems such as tables, bookcases, rugs, furnishings, andyourwoodbox.Allcombustiblematerialsofthistypeshouldbeaminimumof48"(1220mm)fromthefrontsurfaceoftheMerrimackLarge Insert.Besure that familymembersare aware of this requirement as well, so they too will keep objectsasafedistancefromthestove.

Beawarethatachimneyoriginallydesignedforfireplaceusemayperformdifferentlywhenusedtoventanair-controlledappliance such as yourMerrimack Large Insert - even iftheflueislessthan3timeslargerthanthefluecollar.Forexample, a chimney on an outside wall may not heat up enoughtosustainanadequatedraft.Suchafluecanoftenbeimprovedifitisrelinedtoreduceitssizeand/orinsulatedto keep it warmer.• Apositive flue connectionmust bemadebetween the

Insert and the firstmasonry tileor prefabricatedmetalchimneysection.Apositiveflueconnectionconsistsofaplatethatsealsorreplacesthefireplacedamperanda section of chimney connector that passes through the plate into the chimney.

• Thechimneyconnectormustbeaminimumequivalenttoa6"(152mm)diameteropeningandmustbe24gaugeor heavier stainless steel.

ChimneyConnectionsystemsareavailablefromavarietyof manufacturers. Your Vermont Castings dealer can recommendasystemthatwillbestmeettherequirementsof your particular installation.Sealing Requirements / U.S.

• Thechimneymustbesealedofffromroomair,eitherbyaplateatthedamperlevelorbysealingthefireplaceopening.

• Unused openings to the flue must be sealed withmasonrytothethicknessofthechimneywall.Openingssealedwithpieplatesorwallpaperareahazard. Intheeventofachimneyfire,flamesandsmokemaybeforcedfromtheopenings.

In Canada (CAN/CSA-B365-M91, Section 5):• Thisfireplaceinsertmustbeinstalledwithacontinuous

chimneylinerof6"(152mm)diameterextendingfromthefireplaceinsert tothetopof thechimney.Thechimneyliner must conform to the Class 3 requirements of CAN/ULC-S635, Standard for Lining Systems for Existing Masonry or Factory-Built Chimneys and Vents, or CAN/ULC-S640,Standard for Lining Systems for New Masonry Chimneys.

• Theopeningofthefireplacearoundtheinsertmustbesealedtopreventroomairpassingtothefireplacecavity.

• Existingair-circulationchambersinafireplacewithasteellinermaynotbeblocked.

• Provisionmustbemadeforremovaloftheinserttocleanthechimneyflue.

• Theexistingfireplacedamper(ifany)shouldbelockedin the open position.

• Apermanentmetalwarninglabelmustbeaffixedtothebackofthefireplacestatingthefireplacemayhavebeenalteredtoaccommodatetheinsert,andmaybeunsafetouseasaconventionalfireplace.(AFireplaceModificationTagisincludedinthehardwarebaginsidetheMerrimackLargeInsert.)

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 73-90-30004671

Clearance RequirementsAfterconfirmingthatyourfireplaceistherightsize,checktheclearancetocombustibles.Firstmarkwithtapetheexactcenterofyourfireplaceopeningonthehearth.Measuretheside clearance from this point. Measure the top trim and/or mantelclearancesfromthefinishedhearthsurface.Measurethefrontclearance(tofurnishings,etc.) fromthefireplaceface.(Figure4)

X

FP1085WinterWarmclearances3/01

C

A

B

Measure side trim clearance from here

Fireplace Clearances A.Mantel* 43" (1092mm) B.TopTrim(1-1/2”) 41" (1041mm)C.SideTrim** 22-3/4” (578mm)

*Clearanceshownisfor12"(305mm)deepmantel.Dimensionmaybereducedto41"(1041mm)ifthemantelis8"(203mm)deeporless.

** Where side trim extends more than 111⁄22"(38mm)fromthefireplacefacing,thesideclearancemustbenolessthan3111⁄44"(794mm);thisisalso the required side wall clearance.

Measurethesideclearance(C)fromtheexactcenterofyourfireplaceopening on the hearth (X).Measure the top trim (B) and/ormantelclearances (A) from the finished hearth surface.Measure the frontclearance(tofurnishings,etc.)fromthefireplaceface.

Figure 4-Observetheseclearancestocombustibletrim.Hearth RequirementsInsomefireplaces,thehearthinfrontofthefireplaceopeningisbrick,stone,slate,orsomeothernon-combustiblematerialthat is in direct contact with concrete poured over earth. These aretheonlyhearthsthatareconsiderednoncombustible.Inotherfireplaces,thebrickorconcretehearthinfrontofthefireplaceopening issupportedbyheavywooden framing.Because neither brick nor concrete has good insulatingproperties, heat radiated by the fire will pass downwardthrough the hearth to the wooden framing. Such hearths are consideredcombustible.ThehearthfortheMerrimackinsertmustbeconstructedoveracompletelynon-combustiblesurface(suchasunpaintedconcreteoverearth).Thisnon-combustiblehearthmustextendatleast16"(406mm)infrontofthedoorsasprotectionfromheatradiatedfromtheinsert.Thismeansthenon-combustiblehearthmustextend23"infrontofthefireplacefaceopeningin a typical installation.Inaddition,sparkandemberprotectionisneeded8"(203mm)toeachsideoftheinsertandinCanada,18"infrontofthe insert. The approved construction of this protection is a minimum or 24 gauge galvanized sheet metal or equivalent. Figure 5 shows the details of hearth requirements.

FP2492hearth protection7/09 djt

A

C

B B

7”(178 mm)

United States Canada A. 18"* (460mm) 18" (460mm) B. 8" (203mm) 8" (203mm) C. 46-1/2”(1181mm) 46-1/2” (1181mm)

Figure 5-Unlessyourfireplaceandhearthareconstructedoveradirtfloor(orunpaintedconcreteoverdirt),youmustuseafloorprotectorthatsatisfiestheaboverequirements.

Inallcases,thehearthmustbecompletelynoncombustibleinfrontoftheinserttothedimensionsshownandthehearthmustalsobe111⁄22"thickwithk-factorof0.61(R=1.63orequivalent).*IntheUS,iftheinsertiselevated211⁄22"(64mm)ormore,nothermaloremberprotectionisnecessarybeyond16"(406mm).

How to Determine if Alternate Floor Protection Materials are AcceptableAllfloorprotectionmustbenoncombustible(i.e.metals,brick, stone,mineral fiber boards, etc.).Any organicmaterials (i.e. plastics,wood paper products, etc.) arecombustibleandmustnotbeused.Thefloorprotectionspecified includes some form of thermal designation suchasR-value(thermalresistance)ork-factor(thermalconductivity).Procedure:1. ConvertspecificationstoR-value:

i. R-valuegiven-noconversionneeded.ii. k-factor is givenwith a required thickness (T) in

inches:iii. K-factor is givenwith a required thickness (T) in

inches:iv. r-factor is givenwith a required thickness (T) in

inches:R=rxT2. DeterminetheR-valueoftheproposedalternatefloor

protector:i. Use the formula in Step 1 to convert values not

expressed as R.

R=xT1K x 12

R=xT1k

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/208 3-90-30004671

ii. Formultiple layers, addR-values of each layer todetermineoverallR-value.

3. If theoverallR-valueof thesystemisgreater than theR-valueof thespecifiedfloorprotector, thealternate isacceptable.

EXAMPLE:Thespecifiedfloorprotectorshouldbe1-1/2”thickmaterialwithk-factorof0.84.Theproposedalternateis4"brickwithanr-factorof0.2over1/4”mineralboardwithak-factorof0.29Stepa:Useformulaabovetoconvertspecificationto

R-value:

Stepb:CalculateRofproposedsystem. 4"brickofr=0.2,therefore: Rbrick=0.2x4=0.8Step c: 11⁄88"mineralboardofk=0.29,therefore Rmineralboard=x0.25=0.86

Step d: Rtotal=Rbrick + Rmineralboard=0.8+0.86=1.66

Stepe:CompareproposedsystemRtotalof1.66tospecifiedR of 1.79. Since proposed system Rtotal is less than required,thesystemisnotacceptable.

Definitions

Optional Surround PackagesCustom-made surroundpanelsmaybemade fromanynoncombustiblematerial.VermontCastingsGroupoffersasteelorcastironsurroundpanel kit.Installing the Merrimack Large Insert1. Remove or Disable the Fireplace Damper. Ifcodes

allow, remove the damper. Many dampers can beremovedsimplybyremovingacotterpinand/orasetscrew.

Ifitisnotpermissibleorpossibletoremovethedamper,secure the damper in the fully open position.

~ NOTE: CANADIAN INSTALLATIONS ~In accordance with CAN/CSA B365-M91, you must permanently secure the Fireplace Modification Tag to the rear of the fireplace cavity if you have modified the fireplace in any way to accommodate installation of a fireplace insert.ThistagisinthehardwarebagincludedwithyourInsert.2. Flue collar orientation:Thefluecollarmaybeoriented

in the vertical position or rotated 180 degrees on the top ofthestoveresultingina26degreebackwardangle.Ifpossible,determinebeforehandwhichorientationwillworkbestforyourapplication.

r==(ft2)(hr)(°F)(Btu)(in)

1k

(Btu)(ft)(ft2)(hr)(°F)K=

k==Kx12(Btu)(in)(ft2)(hr)(°F)R=

(ft2)(hr)(°F)Btu

R=xT=x1.5=1.791k

10.84

10.29

Figure 6-Componentsoftheventingsystem.

ST1002Vent system components3/08

FlexibleFlueLiner

Flex Liner Adapter (ifrequired)

Adjustable(26"orvertical)FlueCollarw/IntegratedDraw-DownBar

TopoftheInsertAroundFlueOpening

Washers 1/4” Dia.

1/4-20HexNuts

Inmostapplications,cleaningofthechimneysystemwillbeeasiestfromthetop(chimneycap)down.Ifthisistheplannedmethod for your application, the center iron pull down handle onthefluecollarservesasprotectiontopreventachimneybrushfromdamagingthebaffleinsidethestove.Ifcleaningcanonlytakeplacefrominsidethehome,thecenterbarmaybecutoutofthefluecollarusingahacksaworreciprocatingmetal cutting saw.3. Install the venting system: Again, depending on your

applicationitmaybeeasiesttoinstalltheconnectororstainlesssteelfluelinerinthechimneyfirst.RefertoFigure6forthecomponentsoftheventingsystem.

• Carefullyremovethefiberbafflebyfirstremovingthefrontairwashmanifold.Ifnecessary,removetheairtubestoalloweasieraccess.

• Removetheironfluecollarfromthestoveandfasteneithertheadapterpipeorfluelinertoitbydrillingthreeholes using the holes in the iron collar as a guide.

• Securetheflexiblepipetothepipeadaptorusingthesame method.

• Install theconnectorpipeor linerso that theheightmeasuredfromthefinishedhearthsurfacetothecenterbarofthefluecollaris20-1/2”(521mm).(Figure7)This will allow an easy connection once the stove is rolled into place.

4. Route the blower power cord. Run the power cord out theleftorrightsideoftheinsert.Removethetwo(2)louvredoors(Figure9)oraccessdoors.Removethescrewandwasherfromeachsideholdingtheashliptothefront.Ifyou run the power cord out the left side, remove the two (2)screwsholdingtherheostatbrackettothefanhousing.Insertgrommetnearestfanintheslotonthefanhousing,leftorrightside.Reattachrheostatbracketwiththetwo(2)screwsremovedearlier.Removethecoverplateandinsert the provided grommet into the slot. Reattach the cover plate.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 93-90-30004671

Figure 7-Measuredheightfromthefinishedhearthsurfacetothecenterbarofthefluecollar.

20¹⁄₂”(521 mm)

Ref. 26”

ST2493finished height7/09

PossibleHandleBracket Locations

Mantel

Access Door

ST1163merrimack mantel

Bracket and Screws Bracket

and Screws

Figure 8-Securebrackettomantelwithtwo(2)Philipsscrews.

8. Connect the Flue Collar: From inside the stove, reach upandpullthefluecollarintoplacebyliningupthetwo1/4”studsinthestovetop.Careshouldbetakentonotdisturbthegasketwhichsealsthecollartothetop.Tightenthe two 1/4” nuts.

• Replacethestainlesssteelairtubes,ifremoved,byslidingthemfirsttotherightandthenintothematingholesontheleft. Secure these in place with the stainless steel cotter pins.

• Beforeinstallingtheairwashmanifold,replacethefiberbaffleboardandensureitslidesallthewaytotheback.Thereshouldbeatightfitbetweentheboardandtheironsides of the stove.

• Replacethefrontairtubeandsecureitinplacewiththecotter pin.

9. Connect the Blower power cord to the power supply. DO NOT ROUTE THE POWER CORD UNDER OR IN FRONT OF THE UNIT.

10. Install the supplied handle storage bracket by simplyslidingtheflatendundertherightorleftsideofthestove.(Figure7)

ThiscompletesinstallationofyourMerrimackLargeInsert.Smoke and CO DetectorsThe use of smoke and carbonmonoxide (CO) detectorsthroughout the home is strongly advised, even if not required by building codes or insurance regulations.It is a good idea to install a smoke detector in the livingareasandeachbedroom.Follow the smoke/COdetectormanufacture's placement and installation instructions andmaintain regularly.You may not, however, wish to install a detector in the immediate vicinity of the Montpelier insert. Depending on thesensitivityoftheunit,thealarmcanbesetoffwhileyouaretendingthefireoremptyingtheashes.Ifyouinstalladetector in the same room, locate it as far away from the insertaspossible.Safety TipsConvenientlylocatea“ClassA”fireextinguishertocontendwith small fires. Be sure the fire extinguisher works andisclearlyvisible.Alloccupantsof thehouseshouldknowwhereitis,andhowitoperates.Haveheavystoveglovesavailablenear the insert.Havespecialsafetyaccessories(e.g.,ChildGuardScreen)availableforuseifsmallchildrenwillbeinthehome.Intheeventofastovepipeorchimneyfire….• Evacuate the house immediately• Notifythefiredepartment• If thefire isn’t too threatening, closingdown the insert

tight,(damper,primaryair,alldoors)willhelptosmotherthefire.

• Inspect your insert, stove pipe and chimney for anydamage caused by the fire and correct any damagebeforeusingyourinsertagain.

5. Install Mantel and Access Door. For enamel units: Removetheprepackagedmantelandinstallthetwo(2)bracketstotheundersideofthemantelusingfour(4)1/4-20x3/8”Phillipsheadblackscrewsalreadyinstalledinthemantel.(Figure8)Thebracketscanbefoundinthestove.Removethescrewsandusetoattachthebrackets.Forclassicblackunits:Removethetiestrapholdingthemantelinplace.Thebracketsarealreadyattachedtothemantel.Unwrapthetwo(2)pre-assembledaccessdoorsandsnapintoplace.Ifthespacingbetweenthedoorsandupper lattice is not even, you can pull the doors mantel offandadjusttheupperlattice.Screwthetwo(2)jackingscrewsthatcontactthefrontupordownasneeded.(Figure9)

6. Install the Optional Surround Kit. Follow the instructions provided with the kit.

7. Roll the Firebox into Position. At least two people will beneededtomovethefirebox.Toeaseinstallation,liftthe front of the stove slightly to put weight on the rear wheels.Positionthefireboxsothefluecollaralignswiththe connector. Use the leveling screws at the front of the Inserttoadjustthelevel.Routethepowercordtothesidenearest the power supply.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2010 3-90-30004671

OperationYour Insert's Controls and What They DoAllMerrimackLargeInsertcontrolsareconvenientlylocatedonthefront.(Figure9)Three controls regulate the performance of your Merrimack LargeInsert:The primary air controlsuppliesoxygenforthefire.Thevariable-speedfan control, or rheostat, regulates the warmairflowintotheroom.An automatic setback control provides a high air settingof restarting or reviving a fire after reloading and closesautomatically once the stove reaches operating temperatures.

ST1157primary air control

Air Control Lever Open -

Control Lever to the Left

Closed - Control Lever to the Right

Figure 10-Theaircontrollevercontrolstheamountofairenteringthefirebox.

Figure 9 - MerrimackLargeInsertcontrols.

FP2493Merrimack controls

Air Control Lever

FanSpeedControl(Behindlouvre)

Space Between Doors and Upper Lattice

Jacking Screws

Jacking Screws

ST1156fan speed control

Speed ControlOpenBottomLouvreto Access Fan controls

Figure 11-Fancontrolaccess.

WARNING!Thiswoodheaterhasamanufactured-setminimumlowburn rate thatmustnotbealtered. It isagainst federalregulations to alter this setting or otherwise operate this wood heater in a manner inconsistent with operating instructions in this manual.

The FansThe convection fan delivers a steady stream of warm air into theroom.Usethefanspeedcontroltoregulatetheflowofairintotheroom.Athermalswitchwillautomaticallyde-activatethefanwhenthestovecoolsdown.Whenstartingafireina cold stove, this switch will typically energize the fan within about20minutes,afterthestoveheatsup.The fanspeedshouldbesetat "low" (fully closed)whenoperating at low to medium burn rates and may be setanywherebetween"low"and"high"whenoperatingathighburnrates.(RefertoFigure11forfanaccess).

Primary Air ControlAsingleaircontrolregulatestheamountofheatthefirewillproduceandhowlongitwillburn.The primary air control lever is located on the upper left side on the front of the insert. The lever regulates air for starting, maintaining,andrevivingthefire.Generally,moreairenteringthestovemakesthefireburnhotterandfaster,whilelessairprolongstheburn.TheMerrimackLargeInsert'sairsupplyisincreasedwhenthe control lever is moved to the left, and decreased when moved to the right. Itmaybe set anywherebetween thetwo extremes, depending on the amount of heat desired. (Figure10)To complement the manual setting of the air control, the MerrimackLargeInserthasanintegralconvectionairblowerthat ensures an even delivery of heat at the manual setting you select.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 113-90-30004671

Merrimack Large Insert Control Settings

Primary Air Air Circulation

Burn Rate

Control Setting

Fan Speed Control Position

High Fully Left High Horizontal

Medium 1” From Full Right Low Turn Clockwise

Low Fully Right Off Trun Counterclockwise

Use the Air Control Settings that Work Best for YouNosingleaircontrolsettingwillfiteverysituation.Settingsforeach installationwilldifferdependingon thequalityofthe fuel, the amount of heat desired, and how long you wish thefiretoburn.Thecontrolsettingalsodependsonyourparticular"draft,"or the force that moves air from the stove up through the chimney.Draftisaffectedbysuchthingsasthelength,type,andlocationofthechimney,weather,localgeography,nearbyobstructions,andotherfactors.Too much draft may cause excessive temperatures in the MerrimackLarge Insert, and could evendamage internalcomponents.Ontheotherhand, too littledraftcancausebackpuffingintotheroomoraverysluggishfire.Howdoyouknowifyourdraft isexcessivelyhighorlow?Symptomsoftoomuchdraftincludeanuncontrollableburnorglowing-redcastiron.Asignofinadequatedraftissmokeleaking into the room through the stove or chimney connector joints,lowheat,anddirtyglass.Insomenewerhomesthatarewell-insulatedandweather-tight,poordraftmayresultfrominsufficientairinthehouse.Insuchinstances,anopenwindownearthestoveonthewindward side of the house will provide the fresh air needed. Whenfirstusingthestove,keeptrackofthesettingsoftheaircontrols.Youwillquicklyfindthataspecificsettingwillgiveyouafixedamountofheat.Itmaytakeaweekortwotodeterminetheamountofheatandthelengthofburnyoushould expect from various settings.Mostinstallationsdonotrequirealargeamountofcombustionair,especiallyifadequatedraftisavailable.Do not for any reason attempt to increase the firing of your heater by altering the air control adjustment range outlined in these directions.Use the following primary air control lever and fan speed control lever settings as a starting point to help determine thebestsettingsforyourinstallation.

Automatic Setback ControlTheautomaticsetbackaircontrolisusedwhenstartingorrevivingafireandprovidesanincreasedflowofcombustionairtothefireuntilthefireboxissufficientlyheated.Thisairsupply automatically resets to the desired air setting, taking the guesswork out of operating the stove. Figure 9 shows the automatic setback control. Move theprimary air control lever all the way to the left. Push the primary controlaboutonemoreinchtothelefttoopentheairshutter(theleverwillspringbackautomaticallywhenreleased).Theshutterwillremainopenonlyifthestoveisbelowitsproperoperatingtemperature.Onceopen,theprimaryaircontrollevermaybeadjustedtoanydesiredposition.Oncethestoveheats up to its proper operating temperature, you will here a clickingsoundconfirmingtheshutterhasclosed.Thisreturnsthe stove to the output setting of the primary air control.This feature is primarily intended for reloading the stove when lowerairsettings(lowheatoutput)aredesired,butitisalsousefulanytimethefireboxistoocoolforpropercombustionor when freshly added wood does not ignite readily.Formaximumefficiencyandperformance, theMerrimackinsertshouldalwayshavevisibleflamesinnewlyaddedwood,eitherwithinthefuelpileorneartheroofofthefirebox.Woodmoisture,piecesize,draft,weatherandfireboxtemperaturewillallhaveaneffectonhowquicklyflamingoccurs.Theautomaticsetbackaircontrolisaconvenientfeatureallowingmoreuserflexibilityandeaseofoperation.Burn Only High-Quality WoodTheMerrimackLargeInsertisdesignedtoburnnaturalwoodonly;donotburnfuelsotherthanthatforwhichitwasdesigned.You'll enjoy thebest resultswhenburningwood that hasbeenadequatelyair-dried.Avoidburning"green"woodthathasnotbeenproperlyseasonedorcordwoodthatismorethan two years old. Thebesthardwoodfuels includeoak,maple,beech,ash,andhickorythathasbeensplit,stacked,andair-driedoutsideunder cover for at least one to two years.For areas that do not have a supply of hardwood, commonly burnedsoftwoodsincludetamarack,yellowpine,whitepine,Easternredcedar,fir,andredwood.These tooshouldbeproperly dried.YourMerrimackLargeInsertwillacceptwoodupto22"(559mm).Longerwoodpiecesworkbetterthanshortones.Woodshouldbestoredunder cover tomaintaindryness.Even for short-termstorage, however, keepwooda safedistance from the heater and keep it out of the areas around theheaterusedforre-fuelingandashremoval.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2012 3-90-30004671

NOTE:Effectivenessofa“top-down”methodtostartafire.Smoke emissions when starting a fire can be difficult tocontrolbecausetheinsertisnotyetheatedtoitsoptimumtemperature.Onemethodof reducingemissionsduringacoldstart-upistheuseofa“top-down”kindlingprocedure.Inthis,placelargerpiecesofkindlingonthebottomofthekindlingpilefollowedbysmallerandsmallerpiecesasthepileisaddedto.Veryfinelysplitpiecesshouldbeonthetop.Light the kindling pile with a match at the top and allow the kindlingtoburndownwardintothelargerpieces.Thisreducessmokebyslowlyincreasingthefiresizewithoutcreatinganair-starvedcondition.You'llsoonfindthattheinsertisHOT WHILE IN OPERATION! KEEP CHILDREN, CLOTHING, AND FURNITURE AWAY. CONTACT MAY CAUSE SKIN BURNS.NOTE:Somechimneysneedtobe"primed,"orwarmedup,beforetheywilldrawsufficientlytostartafire.Tocorrectthissituation, roll up a couple pieces of newspaper, place them ontopofthekindlingandtowardthebackofthestove,lightthem, and close the doors. This should heat the chimney enough to initiate a draft. Oncethedraftisestablished,openthefrontdoorandlighttherestof thefuel fromthebottom.Donot light themainbedof fuel until the chimneybegins drawing, and repeatthe procedure as often as necessary if the initial attempt is unsuccessful.4. Onceagoodemberbedofatleast3-4"(76-102mm)

has formed, add the desired amount of wood and close theprimaryaircontroltoamedium-lowsetting.Thefirevolumewilldiminishimmediately,buttheMerrimackLargeInsertwillcontinuetoheatup.Maintaincontrolofthefireusingtheprimaryaircontrol,andremember:reducethesetting for less heat, increase the setting for more heat. Refer to the air control settings chart on Page 10 for recommendedsettingsatdifferentburnrates.

Do not over-fire this heater.Overfiring may cause a house fire, or can result in permanent damage to the stove. If an exterior part of the Merrimack Large Insert glows, you are overfiring.Reloading and Reviving a Wood FireSettheaircontrolon"High,"andwaitatleastfifteensecondsforthedrafttoincrease.Turntheconvectionbloweroff.Openthe doors slowly.IMPORTANT: While the stove is hot, toss and sift the coals with each stove loading. This loosens and helps burn coals that become buried in the ash. Push coals away from the bottom air jet. Creating this "void" helps maintain a reliable fire.Check the ash level, and remove excess ash. A primary air holelocatedunderthefrontbrickprovidesairtothecoalbed.(Figure12)Thisholeshouldbeclearedofash forproperperformance.

Starting and Maintaining a Wood FireBurn solid wood fuel only in the Merrimack Large Insert, and burn it directly on the grate. Do not elevate the fuel. Do not burn coal or other fuels. Cast iron isasuperiormaterial forsolid fuelstovesbut itmustbetreatedwithrespect.Itisextremelystrong,butcanbebrokenwitha sharpblow fromahammeror from thethermal shock of rapid and extreme temperature changes. It is importanttotemperthecast ironplateswithaninitialseriesof3-4break-infires.Theplatesexpandandcontractwith changes in temperature.Minimize thermal stress byallowing theplates toadjustgraduallyduring thebreak-infiresbyfollowingSteps1-3onthefollowingpage.

Followtheseguidelinesasyoustartandmaintainthefire,and remove theashes.Prior tostartingafirewithacoldstove, it is recommended to clear the lower primary air hole locatedatthenoseofthefrontbrick.Todothis,removetheandironandliftoutthefrontrefractorybrick.Sweepanyashaccumulation out of the air slot. Keeping this slot clear of ash willensurebetterperformance.1. Opentheprimaryaircontrolfully.2. Layseveralsheetsofcrumplednewspaperinthebottom.

Placeonthepapersixoreightpiecesofdry,finely-splitkindling.Onthekindlinglaytwoorthreelargersticksofsplitdrywoodapproximately1-2"(25-50mm).

Do not use chemicals or fluids to start the fire. Do not burn garbage or flammable fluids such as gasoline, naptha, or engine oil. Also, never use gasoline-type lantern fuel, kerosene, charcoal lighter fluid, or similar liquids to start or "freshen up" a fire in this heater. Keep all such liquids well away from the heater while it is in use.3. Lightthenewspaperandclosethedoor.Graduallybuild

upthefirebyaddingafew3-5"(76-127mm)diametersplits.

Ifthisisyourinitialbreak-infire,letthefireburnbrightly,butnottoexcess.Controlthefire'sintensitybyadjustingtheaircontrol lever. After an hour or so stop adding wood so that thefirediesoutgradually.For ongoing operation after the initial break-in, continueto add a few sticks at a time of a progressively larger size. Besuretokeepthefuelloadbehindthefrontgratebaratalltimes.Continueuntilyouhavealiveemberbedatleast3-4"(76-102mm)deep.Thismaytakeanhourorlonger,particularlywhentheMerrimackLargeInsertisventedtoanexteriormasonrychimneyorwhenyouarejuststartingafire.

WARNING!Operate your Merrimack Large Insert only with the door fully closed. If the door is left partially open, gas and flame may be drawn out of the fireplace opening, creating risks of both fire and smoke.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 133-90-30004671

ST1158front bricks

Primary AirHole

Andiron

Figure 12 - Keep primary air holes free of ash for properperformance.

Tocompensateforthesefactorsincoldclimates,itmaybenecessarytooperatetheMerrimackLargeInsertforlongerperiods of time with the air control set to a higher level more of the time.Remove and Store Ash SafelyChecktheashlevelbeforereloadingthestove,removeashesifnecessary.Turnoffthefanbeforeshovelingtheashintoyour ash container.Remove ash regularly, typically every one to three days. The frequency will vary depending on how you operate your MerrimackLargeInsert;morewoodisconsumedathigherheat output settings, and ash will accumulate faster.Disposal ofAshes -Ash should be removed frequentlyandplacedoutdoorsinametalcontainerwithatight-fittinglid.The closed container of ash should be placed on anon-combustiblefloororontheground,wellawayfromallcombustiblematerials,pendingfinaldisposal.Iftheashisdisposedofbyburialinsoilorotherwiselocallydispersed,itshouldberetainedintheclosedcontaineruntilallcindershavethoroughlycooled.Woodashmaybeusedasagardenfertilizer.

Add the fuel,smallerpiecesfirst. If it isnecessary tousewoodsmallerthanthe18"(460mm)optimumsize,besuretofill thefireboxascompletelyaspossibleby loadingthewood pieces alternately on the left and right. Split wood will fillthefireboxmorecompletelyandreducethefrequencyofreloading.Ifpossible,stackwooddiagonallytomaximizeairspacesbetweenfiredpieces.Ifyouhaveanemberbedofatleast2-3"(51-76mm),theairsettingmaynotneedtobeadjusted.Iftheemberbedislessthan2-3"(51-76mm),activatetheautomaticsetbackfeature.Thiswillprovideextraairtostartthefireflamingand'setback'tothedesiredairsettingoncethestoveisheated.Finally,adjusttheaircontrolandfanspeedforyourdesiredheat level.NOTE:Ifthecharcoalbedisrelativelythickandyourfueliswell-seasoned,itispossibletoaddfreshfuel(smallerpiecesfirst),closethedoor,andresettheaircontrolimmediately.Special Tactics for Cold-Climate HeatingTheMerrimackLargeInsert iscapableofproducingupto55,000 Btu/hour and heating an area of up to 2,000 sq. ft. However,manyfactorsaffectheatingperformanceandcaninfluencetheextenttowhichtheMerrimackLargeInsertcanheat a given area.Awell-insulatedhome, located inamoderateclimateandwiththeMerrimackLargeInsertlocatedcentrallyinanopenfloorplan,willbeeasiertoheatthanadraftyhomeinthefarnorthinwhichaMerrimackLargeInsert isinstalledonanexterior wall at the end of a long house.InFireplace Insert installations, over-sized chimneys canproducelesseffectiveresultsthanthosethatareproperlysized,andinteriorchimneysusuallyperformbetterthanthoselocated outside the house.Different resultsmay be experienced even in the sameinstallationifyouswitchfromburninggood,drywoodtowoodthat is partially rotted or inadequately seasoned.

CAUTION!Never use your household or shop vacuum cleaner to removeashfromthefireplace;alwaysremoveanddisposeof the ash properly.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2014 3-90-30004671

MaintenanceKeep Your Merrimack Large Insert Looking New and Working Its BestCare of the Cast Iron SurfaceAn occasional dusting with a dry rag will keep the painted castironofyourMerrimackLargeInsertlookingnew.Ifthepaintneedsretouching,firstallowthesurfacetocoolcompletely. Mask glass, trim parts and enamelled areas. Wire-brushthoseareastobepainted.Touch-upwithhightemperature stove paint available from your local dealer.Apply thepaint sparingly.Two light coats are better thanone heavy one.Care of the Porcelain Enamel SurfaceUseasoftbrushasnecessary.DonotusewaterorotherliquidsonyourMerrimackLargeInsert.Fingerprintsusuallycan be buffed off porcelain enamelwith a dry, soft cloth.Ifmarksremain,allowtheMerrimackLarge Insert tocoolcompletely, then buffwith a slightly damp, soft cloth.Drycompletelybeforestartingafiretoavoidstreaking.Never use abrasives or harsh chemical cleaners on theporcelainenamelfinish;theenamelmayscratchandexposethecastiron,whichcanthenstainorrust.Ifyoumustremovespillsorstainsfromporcelainsurfaces,makesurethefireisoutandtheMerrimackLargeInserthascooledcompletelybefore cleaning.Use a kitchen appliance cleaner and/orpolishspecificallyformulatedforenamelsurfaces.Applythecleanersparinglywithasoftcloth,andbuffawayalltraces.Cleaning the Glass TheMerrimackLargeInsertglasssystemrequiresaminimumamountofcleaning.Mostcarbondepositsthataccumulatewillburnoffduringhotfires.Ash residue that accumulates on the glass should beremoved periodically to prevent etching. To clean the glass, use the following procedure.

• Be sure the glass is completely cool.• Cleaning with water will work in most cases. Use a

glass cleaner especially made for this purpose only if depositsarespeciallyheavy.(Ifheavydepositsareafrequent occurrence, however, evaluate your operating techniques.)Donotuseabrasivecleaners.

• Rinse the glass thoroughly.• Dry the glass completely.

Figure 13-Rotatepawland/orremoveflatwashertoadjustlatch.

ST1154door pawl

Roller

Lock Nut

Set Screw

Shoulder Screw

HandleStubFlat Washer

Testthedoorseal.Closethedooronadollarbillandattemptto pull it free. If the bill is freedwith little resistance, thegasketisn'tsnugenoughatthatspot.Continuetomakesmalladjustmentsuntilthesettingisright.Ifadditionaladjustingofthelatchdoesnotenablethedoortosealsufficientlyinonearea,try"adjusting"thegasketinthatarea. Pack more cement or a smaller diameter gasket into the channelbeneaththegasketsothemaingasketisraisedandmakescontactwiththedoorframe.Ifthisproceduredoesn'tsolvetheproblem,replacethegasket.Instructionsforgasketreplacement are given later in this section.

Adjust the Door Latch PeriodicallyThefrontdooroftheMerrimackLargeInsertshouldclosesecurely to prevent accidental opening and should close tightly topreventairfromleakingintothefirechamber.Thedoorhandlewillbepositionedverticallywhenthedoorisclosed.Over a period of time, the gasket around the doorwillcompressandthelatchmayneedadjustment.Toadjustthehandle, follow this procedure: 1. Removeand retain the lock nutwith a 9/16”wrench.

(Figure13)2. Loosen the set screw with a 1/8” Allen wrench.3. Rotatethepawl180°.Replacethelocknut.Tightenthe

set screw.4. Additionaladjustmentcanbemadebyremovingtheflat

washer.Oranycombinationofwasher removaland/orpawl rotation.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 153-90-30004671

Removing and Replacing Door GlassFollow this procedure to replace glass.• Openthedoorandloosenthefourretainingclipscrews

that hold the glass to the door. Swing the clips out of the way. Tilt the glass away from the door frame and lift up. (Figure14)Wearglovesandusecautionwhenhandlingbrokenglass.

WARNING!HOT GLASS WILLCAUSE BURNS.

DO NOT TOUCH GLASSUNTIL COOLED.

NEVER ALLOW CHILDRENTO TOUCH GLASS.

AVERTISSEMENT!Un panneau vitré chaud peut

causer des brûlures.Laissez refroidir le panneau

vitré avant d’y toucher.Ne laisser jamais les enfants

toucher le panneau vitré.

• Examine the gasket that seals the glass to the door frame. Ifnecessary,replacethiswithgasketobtainedfromyourlocalVermontCastings’authorizeddealer.Directionsforreplacinggasketsaregivenbelow.

• Checkthechannelatthebottomofthedoorframe,andclearawaydebrisifnecessary.

• Carefully place the new glass in the door frame.• Secure the clips, being careful not to over-tighten.Be

suretheglassisfirmlyseatedagainstthegasket.Closethedoorgentlytoconfirmtheclipshavebeenproperlypositioned.Itispossiblefortheglasstobedamagediftheclipshavebeeninstalledincorrectlyandthedoorisclosed with force.

How to Replace Gaskets YourMerrimackLargeInsertusesrope-typefiberglassgasketstomakeatightsealbetweensomeparts.Withuse,particularlyonthosepartsthatmove,gasketscanbecomebrittleandcompressedandcanbegintolosetheireffectiveness.Thesewill need periodic replacement.Allof thegasketsusedaremadeoffiberglass.The threesizesofreplaceablegasketarelistedbelow,alongwiththeirapplication.

Replaceable Merrimack Large Insert Fiberglass GasketsGasket Size ......................AndThePartsItSeals3/8”(1203589) ..................Doortothefront-4.5'3/8”(30002422) ................Fireboxparts3/16”(1203556) ................Glasstothedoor-4.6'Tochangeagasket,waituntilthefireisoutandthestovehas cooled. Wear protective eyewear and a dust mask. The procedure is the same for all gaskets. 1. Removetheexistingfiberglassgasketbygraspinganend

andpullingfirmly.2. Useawirebrushorthetipofascrewdrivertocleanthe

channelofanyremainingwoodglue,siliconeorbitsofgasket.

3. Apply a thin bead of high temperature silicone to thenewly-cleaneddoorgasketgroove.A1/8”-3/16”beadissufficient.

4. Applyathinbeadofwoodgluetothenewlycleanedglassgasketarea.A1/8”-3/16”beadissufficient.

5. Place a new gasket into the groove. Wait until you have placedallbutacoupleinchesfromtheendbeforeyoutrimtheendtoanexactfit.

Figure 14 - Replace glass.

ST1155replace glass

Door Gasket

Glass GasketGlass Panel

Retainer Clips

IMPORTANT NOTES• DonotoperatetheMerrimackLargeInsertiftheglass

isdamagedorbroken.• Donotabuseglassbystrikingwithanyobjectorby

slamming the door.• Replace glass only with Vermont Castings Group high

temperatureceramicglass,availablefromyourVermontCastings'authorizeddealer.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2016 3-90-30004671

Replacing the Door Gaskets• Removethedoorbyliftingitstraightupfromitshinge

pins.• Lay it face down on a padded surface.• Remove the glass. Follow the instructions for removing

and replacing glass which start on Page 14. • Replacegaskets.Followsteps1-4,above.• Replace the glass.• Replace the door.

The Chimney SystemA Clean Chimney System is Safer and Works BetterAlthough the non-catalytic combustion system in yourMerrimack Large Insert can reduce creosote formationdramatically,itisnotasubstituteforregularinspectionandcleaning of the chimney and chimney connector.Learn to Recognize and Avoid CreosoteYourMerrimackLargeInserthasbeendesignedtominimizecreosote build-up. Regular chimney inspection andmaintenance,however,muststillbeperformed.Forsafety,good stove performance, and to protect your chimney and chimney connector, inspect your chimney and chimney connector on a regular schedule. Clean the system if necessary. Failure to keep the chimney and connector system cleancanresultinaseriouschimneyfire.Creosote-FormationandNeedforRemoval-Whenwoodisburnedslowly,itproducestarandotherorganicvapors,whichcombinewithexpelledmoistuetoformcreosote.Thecreosotevaporscondenseintherelativelycoolchimeyflueofaslow-burningfire.Asaresult,creosoteresidueaccumulateson the flue lining.When ignited, this creosotemakes anextremely hot fire.The chimney and chimney connectorshouldbeinspectedatleastonceeverytwomonthsduringtheheatingseasontodetermineifacreosotebuilduphasoccurred.Ifcreosotehasaccumulated,itshouldberemovedtoreducetheriskofachimneyfire.Ifyoudoexperienceachimneyfire,actpromptlyto:

• Closetheprimaryaircontrollever(fullytotheright).• Get everyone out of the house.• CalltheFireDepartmentfromanearbyhouse.

You should inspect the system every two months during the heating season as part of a regular maintenance schedule. Toinspectthechimney,lettheMerrimackLargeInsertcoolcompletely. Then, using a strong light, sight up through the fluecollarintothechimneyflue.Thefiberbafflewillneedtoberemovedgentlytoviewinsidetheconnectorpipe.

If it isnecessary to remove thefirechamber to inspectorclean the chimney, this is how to do it:

• LettheMerrimackLargeInsertcool.• Disconnect the fan power cord.• Youmaywishtolightenthefireboxbyremovingthe

load door and andiron.• Retract the two levelling screwsuntil they bear no

weight.• Removethefrontairtubeandfiberbaffle.• Disconnectthefluecollarorventconnectorfromthe

top of the stove.• Slidethefirechamberforwarduntilyouhaveaccess

tothefireplaceopening.• Inspecttheflue.

Youcannowinspectthesmokeshelfareaofthefireplaceandthechimney.BeforereplacingtheMerrimackLargeInsert,thisareashouldbeinspectedforsignsofdeteriorationandcleanedthoroughlywithachimneybrush.Cleanthechimneyusingaspeciallydesignedbrushthesamesizeandshapeastheflueliner.Flexiblefiberglassrodsareusedtorunthebrushupanddowntheliner,causinganydepositstofalltothebottomofthechimneywheretheycanberemovedthroughtheclean-outdoor.Thechimneyconnectorshouldbecleanedbydisconnectingthe sections, taking them outside, and removing any deposits withastiffwirebrush.Reinstalltheconnectorsectionsaftercleaning,beingsureto secure the individual sections with sheet metal screws.Ifyoucan'tdothechimneyinspectionyourself,contactyourlocal VermontCastings'AuthorizedDealer, or engage aprofessional chimney sweep to perform the inspection and cleaning of the chimney.Reversetheproceduretore-installthefirechamber.

Fireplace System Maintenance ScheduleFireplace:Daily:

• Ashshouldberemovedbeforethelevelreachesthetopedgeofthefrontbrick.Checkeachtimeyoure-load, or at least once a day.

• Keep the area around the fireplace clear of any combustiblematerial.

Yearly Spring Cleaning:• Remove ash from the firebox and replacewith a

moisture-absorbingmaterial (such as kitty litter) tokeep the interior of the stove dry.

• Touchuppaintedsurfaceswithblackpaint.

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/20 173-90-30004671

Forpartsandinformationaboutyourinsert,contactyourVermont Castings authorized dealer. For the name of the dealer nearest you, visit: www.vermontcastings.com

Optional Accessories

45⁷⁄₈” (1165 mm)

32⁵⁄₃₂” (817 mm)

ST1161Exeter surround

Exeter Steel SurroundNorthfield Cast Iron Surround

32³⁄₁₆”(818 mm)

46¹⁄₁₆" (1170 mm)

ST1160Northfield surround

Flex Connection:Two Months:

• Inspect thechimneyandflueconnection.Clean thesystem if necessary.

Yearly Spring Cleaning:• Disassembletheflueconnectionandtakeitoutdoors

for inspection and cleaning. Replace weak sections of connector.

• Inspect the chimney for signs of deterioration.Repairstoamasonrychimneyshouldbemadebyaprofessional mason. Replace damaged sections of prefabricatedchimney.YourlocalVermontCastings'dealer or a chimney sweep can help determine when replacement is necessary.

• Thoroughly clean the chimney.

Northfield Cast Iron SurroundModel ColorNORCSCB Classic Black

Exeter Steel SurroundModel ColorEXSSCB Classic Black

Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2018 3-90-30004671

Hearth & Home TechnologiesLIMITED LIFETIME WARRANTY

Hearth & Home Technologies, on behalf of its hearth brands (“HHT”), extends the following warranty for HHT gas, wood, pellet and electric hearth appliances that are purchased from an HHT authorized dealer.WARRANTY COVERAGE:HHT warrants to the original owner of the HHT appliance at the site of installation, and to any transferee taking ownership of the appliance at the site of installation within two years following the date of original purchase, that the HHT appliance will be free from defects in materials and workmanship at the time of manufacture. After installation, if covered components manufactured by HHT are found to be defective in materials or workmanship during the applicable warranty period, HHT will, at its option, repair or replace the covered components. HHT, at its own discretion, may fully discharge all of its obligations under such warranties by replacing the product itself or refunding the verified purchase price of the product itself. The maximum amount recoverable under this warranty is limited to the purchase price of the product. This warranty is subject to conditions, exclusions and limitations as described below. WARRANTY PERIOD:Warranty coverage for consumers begins at the date of installation. In the case of new home construction, warranty coverage begins on the date of first occupancy of the dwelling or six months after the sale of the product by an independent, authorized HHT dealer/distributor, whichever occurs earlier. However, the warranty shall commence no later than 24 months following the date of product shipment from HHT, regardless of the installation or occupancy date. The warranty period for parts and labor for covered components is produced in the following table.The term “Limited Lifetime” in the table below is defined as: 20 years from the beginning date of warranty coverage for gas appliances, and 10 years from the beginning date of warranty coverage for wood and pellet appliances. These time periods reflect the minimum expected useful lives of the designated components under normal operating conditions.

Page 1 of 24021-645K 1/20

Parts Labor Gas Pellet Wood Electric Venting Components Covered

X X Igniters, Auger Motors, Electronic Components, and Glass

XElectrical components limited to modules, remotes/wall switches, valves, pilots, blowers, junction boxes, wire

harnesses, transformers and lights (excluding light bulbs)

X X Molded Refractory Panels, Glass Liners

X Vent Free Burners, Vent Free Logs

X X Castings, Medallions and Baffles

6 years 3 years X Catalyst - Limitations Listed

7 years 3 years X X Manifold tubes, HHT Chimney and Terminations

10 years 1 year X Burners, logs and refractory

Limited Lifetime 3 years X X X Firebox and heat exchanger, FlexBurn® System

(engine, inner cover,access cover and fireback)

1 Year None X X X X X All replacement parts beyond warranty period

Warranty Period HHT Manufactured Appliances and Venting

All parts including handles, external enamaled components and other material except as covered by

Conditions, Exclusions, and Limitations listed

2 years

3 years X

X1 Year X X X X

5 years 1 year

Firepots, burnpots, mechanical feeders/auger assemblies

See conditions, exclusions and limitations on the next page

WARRANTY CONDITIONS:• This warranty only covers HHT appliances that are purchased through an HHT authorized dealer or distributor. A list of HHT

authorized dealers is available on the HHT branded websites.• This warranty is only valid while the HHT appliance remains at the site of original installation.• This warranty is only valid in the country in which the HHT authorized dealer or distributor that sold the appliance resides.• Contact your installing dealer for warranty service. If the installing dealer or distributor is unable to provide necessary parts,

contact the nearest HHT authorized dealer or supplier. Additional service fees may apply if you are seeking warranty service from a dealer other than the dealer from whom you originally purchased the product.

• Check with your dealer in advance for any costs to you when arranging a warranty call. Travel and shipping charges for parts are not covered by this warranty.

• Limited Catalyst Warrantyo For wood burning products containing a catalyst, the catalyst will be warranted for a six-year period to the original purchaser at

the site of original installation. The purchaser must provide the name, address, and telephone number of the location where the product is installed, proof of original purchase date, date of failure, and any relevant information regarding the failure of the catalyst.

WARRANTY EXCLUSIONS:This warranty does not cover the following:• Changes in surface finishes as a result of normal use. As a heating appliance, some changes in color of interior and exterior surface

finishes may occur. This is not a flaw and is not covered under warranty.• Damage to printed, plated, or enameled surfaces caused by fingerprints, accidents, misuse, scratches, melted items, or other

external sources and residues left on the plated surfaces from the use of abrasive cleaners or polishes.• Repair or replacement of parts that are subject to normal wear and tear during the warranty period are not covered. These parts

include: paint, wood and pellet gaskets, firebricks, grates, flame guides, batteries and the discoloration of glass. • Expansion, contraction, or movement of certain parts causing noise. These conditions are normal and complaints related to this

noise are not covered by this warranty.• Damages resulting from: (1) failure to install, operate, or maintain the appliance in accordance with the installation instructions,

operating instructions, and listing agent identification label furnished with the appliance; (2) failure to install the appliance in accordance with local building codes; (3) shipping or improper handling; (4) improper operation, abuse, misuse, continued operation with damaged, corroded or failed components, accident, or improperly/incorrectly performed repairs (5) environmental conditions, inadequate ventilation, negative pressure, or drafting caused by tightly sealed constructions, insufficient make-up air supply, or handling devices such as exhaust fans or forced air furnaces or other such causes; (6) use of fuels other than those specified in the operation instructions; (7) installation or use of components not supplied with the appliance or any other components not expressly authorized and approved by HHT; (8) modification of the appliance not expressly authorized and approved by HHT in writing; and/or (9) interruptions or fluctuations of electrical power supply to the appliance.

• Non-HHT venting components, hearth connections or other accessories used in conjunction with the appliance.• Any part of a pre-existing fireplace system in which an insert or a decorative gas appliance is installed.• HHT’s obligation under this warranty does not extend to the appliance’s capability to heat the desired space. Information is provided

to assist the consumer and the dealer in selecting the proper appliance for the application. Consideration must be given to the appliance location and configuration, environmental conditions, insulation and air tightness of the structure.

This warranty is void if:• The appliance has been over-fired, operated in atmospheres contaminated by chlorine, fluorine, or other damaging chemicals.

Over-firing can be identified by, but not limited to, warped plates or tubes, deformation/warping of interior cast iron structure or components, rust colored cast iron, bubbling, cracking and discoloration of steel or enamel finishes.

• The appliance is subjected to prolonged periods of dampness or condensation.• There is any damage to the appliance or other components due to water or weather damage which is the result of, but not limited

to, improper chimney or venting installation.

LIMITATIONS OF LIABILITY• The owner’s exclusive remedy and HHT’s sole obligation under this warranty, under any other warranty, express or implied, or in

contract, tort or otherwise, shall be limited to replacement, repair, or refund, as specified above. In no event will HHT be liable for any incidental or consequential damages caused by defects in the appliance. Some states do not allow exclusions or limitation of incidental or consequential damages, so these limitations may not apply to you. This warranty gives you specific rights; you may also have other rights, which vary from state to state. EXCEPT TO THE EXTENT PROVIDED BY LAW, HHT MAKES NO EXPRESS WARRANTIES OTHER THAN THE WARRANTY SPECIFICED HEREIN. THE DURATION OF ANY IMPLIED WARRANTY IS LIMITED TO DURATION OF THE EXPRESSED WARRANTY SPECIFIED ABOVE.

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Vermont Castings • Merrimack Large Insert Owner’s Manual_R19 • 03/2020 3-90-30004671

352MountainHouseRoad•Halifax,PA17032www.vermontcastings.com