1. Starting prices have been provided by a manufacture or a manufacturer's dealer and are believed to be accurate at the time of publishing. They may change at any time. For official pricing, always contact a manufacturer or dealer directly. Prices for Nature's Comfort have been publicized as "Introductory."
2. Measured in lb/mmBTU. Lower emission ratings are better. Must be below 0.32 to be EPA certified after Dec. 31, 2015.
   See official emissions ratings on all EPA Step 1 certified furnaces at www.epa.gov/compliance/list-epa-certified-hydronic-heaters.
3. For EPA Step 1 certified furnaces, "Max BTU" refers to the "Max Heat Output Rating (BTU/hr)" number provided by the EPA. For all other furnaces, numbers reflect information provided by the manufacturer or one of its dealers. BTU output can vary widely depending on many factors. These numbers are provided solely for furnace size comparison and should not be used to calculate actual output for the typical owner.
4. These Central Boiler models are not listed by the EPA on their official list of certified residential heaters (dated January 2016) and do not have an EPA rating.
5. Central Boiler's limited warranty covering Edge and E-Classic models warrant firebox corrosion for 10 years. Defects in the workmanship of a Central Boiler firebox are covered for 25 years.

One of the most important things to consider when buying an outdoor wood-burning furnace is the warranty. Like buying a car, a warranty can be the difference between a working machine and a $10k pile of scrap metal. If properly maintained, a well-manufactured wood-burning furnace should last several decades.

Is a warranty really that important?

Yes! We have been in this business a long time, and we have seen a lot of poorly made stoves. We have found that the warranty of a furnace usually reflects its quality, and a good warranty can protect you from catastrophic failures that leave you cold in the dead of winter.

Because warranties vary drastically from brand to brand, and warranties can be notoriously hard to research, we have done the work for you and put together some of the key points from all the major manufacturer warranties... You're welcome.

What is the most important thing to know about warranties?

As you might guess, the most important thing with any warranty is coverage. All furnace warranties are "limited," but each manufacturer has different limits, conditions, and terms. For example, Central Boiler^TM has a 25-year limited warranty, but the firebox is only warranted for 10 years. Heatmor^TM has a lifetime warranty, but they cover only 15% of the replacement value after 10 years.

Who has the best coverage?

Hawken Energy has the best warranty coverage in the industry.

If you are like most customers, an outdoor furnace is an investment. You want a furnace that will save you money immediately on your heating bills, but also one that will last more than just a couple of years. One of the things that you should consider is the material used to manufacture your furnace.

There are three important things to consider when looking at the steel of an outdoor wood furnace.

Type of Steel - The type of steel used in a furnace determines the efficiency and durability of your furnace, and has a large impact on the price.

Thickness of Steel - The gauge, or thickness, of the steel also affects the price of a furnace, as well as its ability to transfer heat. Generally, a manufacturer will use thinner steel for parts that are less susceptible to abuse and/or corrosion. Hawken uses 1/4" steel for the firebox assembly and other key parts, which provides a good balance of heat transfer efficiency and durability.

Grade of Steel - Even for particular types of steel, there are different grades or quality levels. This is determined by the standards used in the production, selection, and melting of the raw steel.

In our research, we have found that there are three types of steel used in outdoor wood-burning furnaces:

The kind of steel used to make your furnace will determine the efficiency (how well heat can be transferred from the fire to the water that heats your home), the durability (how susceptible it will be to rust and corrosion), and the price of your furnace. Be careful that you do not pay more for a type of steel that does nothing for you!