Are you considering purchasing an outdoor wood furnace? Please take a fewminutes and read through this information. We will compare feature byfeature why Central Boiler® produces the best outdoor wood furnaces on themarket and is the industry leader. With this brochure, you will understand12 reasons why the Central Boiler Classic® Outdoor Wood Furnace isunmatched in efficiency, quality, and reputation.

centralboi ler.comcentralboi ler.com

Large exterior water jacket surfaceareas result in excessive heat loss to theoutdoors. The firebox is undersized inrelationship to the water jacket andmakes for very short burn times. Smallexhaust flues necessitate a forced draft.These small flues require constantcleaning for the furnace to operate.

There is no secondary burn chamber as the transition inthe back of the furnace does not maintain a high enoughtemperature to support combustion.

This is another competitor’s designutilizing a top-exiting chimney that pullsthe heat out of the firebox before heat canbe transferred to the water. Again,because of inherent problems associatedwith top exiting chimneys, the waterjacket may experience corrosion. The

exhaust flue tube, like above design, collects creosoteand makes cleaning awkward. The bottom of fireboxprovides no heat transfer area and is filled with grates, sandor gravel.

The door in this example isextremely heavy and iscumbersome to open, close,and latch. This designallows wood and coals tospill out of firebox whenopened. Also the door sealis poorly designed.

Firebox DesignFirebox Design DoorDoor

2 centralboiler.com

Other Designs-Inefficient Heat Transfer

Classic-Revolutionary Design Classic-Revolutionary Design

21

C

B

Cam Loc®

Natural Draft

Cast Iron Door

Top exiting chimneys do not permitadequate time for gases to complete thecombustion process and maximize heattransfer. Top exiting chimneys alsoallow moisture to enter around thechimney pipe causing corrosion on theexterior of the water jacket. This design

uses outdated heat transfer tubes that make cleaningdifficult and may result in corrosion. A cylindrical fireboxmay collapse against pressure from surrounding water.

A Other Designs-A Variety of Shortcomings

E

Featuring a durable design, the Classic offers an insulatedcast iron door that is built to last. The Classic’s Cam Loc®

door closure allows for easy opening and ensures a tight,well-sealed closure.

There are a multitude of door problems plaguing otheroutdoor wood furnaces. Some of these include cumber-some door latch operation, warping, poor insulationtechniques and inadequate sealing.

Classic -Insulated Cast I ronClassic -Insulated Cast I ron

The Ripple Top® and HeatLock Baffle® producemaximum heat transfer. This design “raised the bar”and created a new standard for the wood heatingindustry. The Classic is unmatched in efficiency andease of use. Our exclusive HeatLock Baffle creates asecondary burn area where gases are trapped in the topof the firebox for optimum combustion. A water jacketsurrounding the entire firebox allows heat transfer from

all sides including thecoal bed. The chimneyexits out the rear ofthe firebox eliminatingcorrosion competitorsexperience from top-exiting chimneys.

This design has severaldrawbacks. The outer doorattempts to reduce heat losswith extremely low R-valueinsulation. Rubber hosesconnected to the water filledinner door continually bendand can crack or fail causingdamage to the furnace.

Awkward door location makes lighting a fire, loadingwood, and cleaning out of ashes with a shovel (when theauger fails) a hassle.

D

Ripple Top®

HeatLock Baffle®

3

This illustration shows a chimney exiting out the top ofa furnace through the tin roof. With this design, thehigh chimney temperature causes the caulking to loosenor burn off. This results in moisture penetrating theenclosure causing corrosion to the water jacket,chimney base, and a depletion of the fiberglass battinsulation’s R-value.

Many other manufacturers offer fiberglass battedinsulation. Fiberglass batts are inefficient, allow air toblow through, and leave gaps at the joints. This type ofinsulation is usually placed or wrapped loosely aroundthe water jacket and allows heat to escape and createcondensation. In addition, most of these furnaces workin conjunction with top-exiting chimneys. Once thecaulking burns away, the insulation will be soaked withrain and moisture.

ChimneyChimney InsulationInsulation

To assure the heat stays in the water jacket, CentralBoiler® uses the most advanced insulating material.Spray on urethane is the best type of insulationavailable. It is waterproof, airtight, will not settle orshift, and has the highest R value available per inch ofany insulation. Central Boiler applies a layer of up tosix inches around the water jacket. The Classic’ssprayed on urethane insulation will not break down andis rated for temperatures that far exceed that of thewater jacket operating temperatures.

centralboiler.com

43

The Classic’s chimney exits the rear of the furnaceeliminating the roof leakage associated with top exitingchimneys. A large exhaust passage with removablecleanout reduces maintenance and allows natural draft tooperate properly. This certified, factory-built chimney isinsulated to eliminate condensation and is tested to 1800˚F.The standard 8-foot length improves draft and efficiency.

Insulated Chimney

ConvenientRear Access

Classic-Sprayed on Urethane FoamClassic-Sprayed on Urethane FoamClassic -Rear Exit ing & InsulatedClassic -Rear Exit ing & Insulated

Other Designs-Top Exiting & Prone to Leaks

Other Designs-Batts and Gaps

4

Other companies continually make the simple procedureof cleaning ashes from the firebox a difficult task.Augers, grates, drawers, and removable ash pans allhave three things in common; 1.) moving parts thatbreak down 2.) hassle 3.) mess. In the above pictures,Figure F uses an auger and grate ash removal system.Frequently the outlet is buried in snow or ice thatneeds to be shoveled or chipped to be accessed. This isonly the beginning. The user must continually walkback to the firebox door to push the ashes through thegrates. Frequently, the auger will jam with coals ornails. Figure G features a drawer over 6 feet long thatweighs about 45 pounds empty and can weigh up to 100pounds when full. These “features” create more workand less convenience.

Ash RemovalAsh Removal MaterialsMaterials

Central Boiler® outdoor wood furnaces are constructedfrom high quality materials. Top grade carbon steel ensuresthat all Classic furnaces are constructed from premiumgrade materials. State-of-the-art CNC machines cut andform the material with unmatched precision. At CentralBoiler, higher standards and superb manufacturing techniques result in a proven end product.

centralboiler.com

5 6

No gimmicks --nothing to break or stick. An ergonom-ically friendly design makes ash removal simple --outthe front door with a shovel. The large door and angledash-pan allow hassle-free clean-out.

Classic -No Moving Par tsClassic -No Moving Par ts Classic -Higher StandardsClassic -Higher Standards

F

G

Other Designs-Hassle and Mess

Other Brands-Caution!

Some outdoor wood furnace manufacturers use impropermanufacturing techniques. For example, weldingdissimilar metals together. This manufacturing practicecreates electro-chemical reactions in an outdoor woodfurnace environment resulting in premature corrosionfailures. Another manufacturer uses unsuitablemetals --such as 304L stainless, referred to by someas “dairy grade.” 304 is suitable in a number ofapplications but not outdoor wood furnaces. Metallurgyconsultants advised Central Boiler that 304 gradesof stainless are not a suitable choice for outdoor woodfurnace applications. In the early 1990s, CentralBoiler’s Research and Development testing confirmed304 grade failures within 4 years (as predicted). Formore information on stainless steel comparisons visitwww.centralboiler.com/stainless.html.

Picture of 304 stainless from actual outdoor wood furnace

Fuel oil must be of proper viscosity to operate correctly.

5

The “solid protection” offered in the warranties ofother manufacturers do not reflect the same confidencein their product as the Central Boiler warranty does.Here are some examples of where they fall short: Oneparticular manufacturer requires the user to send watersamples into a certified lab twice a year or the warrantyis void. Some manufacturers completely excludecorrosion from their warranty. One manufacturer thatoffers an auger and grate ash removal system onlywarrants it for one year. Many cover manufacturingdefects for as little as three years and most otherwarranties do not cover labor costs.

You are now able to order adual fuel ready furnace thatallows the furnace to be fittedwith a Fuel Oil, Natural Gasor Propane burner. The DualFuel System has four modesof operation; Wood Only,Clean Start™, Dual FuelBackup and Fuel Oil/LP/NG.Laboratory tests have shown

efficiencies over 85%. The Clean Start mode allows theDual Fuel burner to operate for a short period of time toimmediately create secondary combustion within theRipple Top® and HeatLock Baffle® firebox design. In theDual Fuel Backup mode, the burner will automatically fireitself when the wood supply in the firebox is depleted,keeping your home warm even if you are not there to loadwood into the furnace. This flexible Dual Fuel systemallows you to adapt the furnace to your individual heatingneeds.

WarrantyWarranty Dual Fuel SystemDual Fuel System

Central Boiler® has been building Classic outdoor woodfurnaces since 1984 and has grown to be the largestmanufacturer of outdoor wood furnaces in NorthAmerica. We are a stable company that believes in theClassic. Through our warranty we pass that confidenceon to you, the consumer. The Classic has a 25 YearLimited Warranty available, which includes a 10 yearlimited corrosion warranty, which is the best in theindustry. Central Boiler’s dedication to quality productsand customer satisfaction is what makes this outstandingwarranty possible.

centralboiler.com

Model CL 6048With Dual Fuel Burner Installed

7 8

Classic -UnmatchedClassic -Unmatched Classic -High Eff ic iency BackupClassic -High Eff ic iency Backup

Other Brands-Exclusions & Illusions

When looking for an outdoor wood furnace, we encourageyou to look closely at the different warranties thatmanufacturers offer. We are confident that you willfind the Classic’s warranty is the best. Central Boiler’swarranty is just another illustration of our commitmentto quality and why the others are fighting for a distantsecond place.

6

Research and Development form a very important part ofCentral Boiler, Inc. In 1984, the design of the originalCentral Boiler outdoor wood furnace was developed. Sincethen quality and innovation have been an ongoing goal ofthe Central Boiler Research and Development team.Constant testing, continued improvement, and the desire tocreate the best, drive a dedicated group of highly skilledengineers and technicians. As a result, Central Boiler has areputation for producing a high quality and efficient productand has grown to be the largest manufacturer of outdoorwood furnaces in North America. Over the years, they havedeveloped many industry firsts including the exclusive

Ripple Top® design, HeatLock Baffle®, and a long awaitedreliable dual fuel system. The talented R&D team developsand tests products before the changes reach the assemblyline. You as a consumer can be assured that the testing isdone in R&D –not on the final product. The Central BoilerR&D Department has the most complete testing laboratoryin the outdoor wood furnace industry, which is equippedwith state-of-the-art equipment and the latest in technology.This facility has the ability to collect and analyze a widerange of data, including emissions and efficiency. CentralBoiler’s R&D is responsible for ensuring that all productscan be used safely. The R&D team works closely withthird-party organizations, such as Underwriters Laboratories(UL) and OMNI-Test Laboratories Inc., to have productstested and listed for safety. At Central Boiler, research,development, testing and refining is a part of the everydayprocess –not a one-time event.

Research and Development Department / Test Laboratory Research and Development Department / Test Laboratory

centralboiler.com

Combustion Laboratory shown with efficiency andemissions data collection equipment

Combustion Laboratory shown with efficiency andemissions data collection equipment

Quality and Durability are Built into Every Classic ModelQuality and Durability are Built into Every Classic Model

9

7

PerformancePerformance

centralboiler.com

Don’t Be Mislead by Inaccurate ComparisonsDon’t Be Mislead by Inaccurate Comparisons

Central Boiler is the company that sets the benchmarksfor the outdoor wood furnace industry. As a result,many other manufacturers continually compare theirfurnaces to the Classic. However flattering, this canbe confusing and misleading for customers. Whenevaluating different furnaces, beware of inaccurate sizecomparisons. Some manufacturers stress watercapacity. An excessive capacity of water doesn’tnecessarily improve furnace performance. In fact, whencombined with a small firebox volume, it leads to a

decreased burn time and increased heat loss. Othershave a water volume that is too low for safe operation.The Classic provides a proven balance between fireboxvolume and water capacity for optimum performanceand safety. Another comparison inaccuracy is pricing.When competing for price, others will often quote afurnace with a smaller heating capacity. If you receivea quote from a competitor that is significantly lowerthan a quote on a Central Boiler furnace, most likelyyou are comparing furnaces of a different size.

Even though some furnaces may appear similar in size, they don’t compare equally to the Classic for delivered performance.

Heat coefficient is a result of the relationship betweendelivered efficiency, heat transfer effectiveness, heatloss, and useable firebox volume.

Manufacturers may change furnace designs

10

©2007 Central Boiler® ™ Trademarks of Central Boiler, Inc.Printed in the United States 8/07Content of this brochure is information in possession of Central Boiler at thetime of the design of this publication. Product specifications and appearancesubject to change.Consider location and direction smoke may travel with prevailing windsbefore installing your furnace.p/n 2487

Central Boi ler, Inc.20502 160th St reet • Greenbush, MN 56726

Parts and AccessoriesParts and Accessories Quality and CommitmentQuality and Commitment

When it comes to installing youroutdoor wood furnace, we carrya complete line of parts andaccessories. Central Boiler hasdedicated thousands of squarefeet to radiant heat components,pumps, water-to-air and water-to-water heat exchangers, airhandling cabinets, radiant base-boards, flange kits, Central

PEX® tubing, manifolds, thermostats, zone valves, ballvalves, and much more. Our dealer network can accessall of these components with FedEx, Spee-Dee, UPSand other carriers for timely delivery in order toserve you better.

11 12

Thank you for taking the time to look over this information.If you have further questions about our products, pleasetalk to your local Central Boiler dealer or log ontocentralboiler.com, and reference the dealer locator.At Central Boiler we are committed to you the customer,the environment and your family’s warmth, comfort andsafety.

centralboiler.com

Fully Stocked and Ready to ShipFully Stocked and Ready to Ship American Craftsmanship and PrideAmerican Craftsmanship and PrideCentral Boiler has been building outdoor wood furnaces in Northwestern Minnesota since 1984.With unsurpassed quality and commitment, CentralBoiler, Inc. has become synonymous with woodheating and has subsequently grown to be thelargest manufacturer of outdoor wood furnaces inNorth America. At Central Boiler we believe qualityproducts are a direct result of qualified individualsworking together for a common accomplishment: A high quality finished product with an economicbenefit for the consumer.

Your Authorized Central Boi ler Dealer