Wood Heater Buyer's Guide
- Modern wood heater design
Heating technologies come and go, but wood-burning heaters have remained a popular choice throughout the centuries. Modern technology enhances these classic heaters, making them more efficient, cleaner, and eco-friendly. Whether you're looking for a fireplace insert, wood stove, pellet stove, or wood-burning forced-air furnace, you'll appreciate this merging of modern technology and classic heating.
EPA-compliant wood-burning heaters burn far cleaner and more efficiently than traditional fireplaces. Not only does this mean better air quality, but your fuel also lasts longer. For those who have easy access to firewood, wood heaters are a durable, cost-effective way to supplement your heat. They also work well for more remote locations that don't have access to natural gas lines or electricity.
What Are Wood Heaters?
The most basic definition for a wood heater is anything that burns wood to generate heat. Under this category, there are many different types including freestanding stoves, fireplace inserts, closed combustion fireplaces, and furnaces. Some are designed to add a little ambient warmth, while others heat the entire home.
The various designs make it possible to choose a wood heater that fits your style, budget, emissions preference, and heating needs. Here's a quick overview of the main categories.
- Freestanding wood stove
Freestanding stoves may be used as a primary heating source or to add supplemental heat. Some people even use them for cooking. They are typically made from metal (sometimes stone) and burn wood in a chamber.
Wood-burning stoves are an excellent choice for anyone with easy access to firewood. They don't require any electricity unless the stove is equipped with a blower. If the stove has a blower fan, it requires a 120-volt power source.
- Wood fireplace insert
Wood fireplace inserts are essentially wood stoves built to fit inside an existing fireplace opening. They are also called wood stove inserts. Their main purpose is to convert low-efficiency traditional fireplaces into high-efficiency heat sources. Please note that most are designed to insert into an open-faced fireplace.
Inserts have a sealed firebox with a smaller window to view the fire. However, what you lose in flame aesthetics, you gain in heating efficiency. Wood-burning stoves are subject to EPA regulations and have very low emissions compared to traditional fireplaces or stoves.
High-Efficiency Closed Combustion Fireplaces
- High-efficiency wood-burning fireplace
Closed combustion fireplaces are similar to fireplace inserts except that they are not installed in an existing fireplace. Instead, you can use them to construct a brand new fireplace.
Unlike open-faced traditional fireplaces, closed combustion fireplaces only use a tiny fraction of the room air. This achieves a very clean and efficient burn. Like the fireplace inserts, the design limits the viewing area, but it makes up for it in low emissions and excellent heating capability.
Since they burn wood, high-efficiency fireplaces are a good option for heat during a power outage. Unless they rely on electrically-powered blower fans, they are able to operate without electricity.
- Drolet wood furnace
Furnaces are designed to provide substantial heat to the home. Homes with wood stoves often use them to supplement a gas heating system. Wood furnaces function similar to a wood stove, but the design favors practicality over style.
A typical wood furnace houses a steel wood-burning stove inside a sheet metal cabinet. The gases or other emissions escape through a vent system and the air inside the metal cabinet is heated and distributed throughout the home via ducts. For best results, the wood furnace should be beside the HVAC system so that hot air can be blown through the ducts efficiently.
The furnace is loaded with wood like a stove, and there are controls to adjust the amount of air intake. Like wood stoves, they require venting through a chimney pipe.
Wood-burning furnaces are an excellent way to save money on heating costs if you can source inexpensive firewood. They also work well for areas where gas or other heating options are not readily available. The drawbacks are that they take up space and require more effort and maintenance than most modern heating systems.
What To Know Before You Buy
When it comes to wood heaters, there are so many options that it can be hard to know where to start. We'll go through some ways to help narrow down your decision. Let's start with some of the things you should consider before deciding if a wood-burning appliance is right for you.
What Are Your Local Codes And Restrictions?
Many states and local authorities have rules and regulations concerning wood-burning appliances. A few areas even ban wood-burning appliances altogether. Always check to make sure you know what the restrictions are before purchasing a wood-burning stove or fireplace insert. You can do this by contacting your local Department of Environmental Quality.
- EPA Seal
You also need to consider the EPA standards. As of February 3, 2015, all new stoves were limited to emit no more than 4.5 grams of pollution per hour. By May 1, 2020, that standard is scheduled to be reduced to just 2.0 grams per hour.
Homeowners associations may have their own restrictions for wood-burning appliances. We recommend checking with your HOA before making any purchases.
What Are The Health Considerations?
The tiny particles released into the air from burning wood may irritate people with allergies or respiratory issues. Smoke pollution could potentially harm the lungs, blood vessels, and heart. Many of the modern wood heaters burn very cleanly, but this is still something to consider if someone in the home is particularly sensitive to air quality.
What Are The Benefits of Wood Fuel?
Depending on where you live, wood fuel is a cheap and plentiful fuel source. It is also carbon-neutral (unlike natural gas or propane), so it has a smaller carbon footprint. Many people also appreciate the advantage of stockpiling wood during the summer when it is cheaper. Our article on buying firewood has information on calculating how much you'll need for the winter.
Which Wood Heater is Best For You?
Once you decide you want to go with a wood-burning appliance, how do you know which one to get? Here are six considerations to help you find the type of wood heater that works best for your home. We'll look at the configuration, venting, cost, heat output, efficiency, and materials.
What Configuration Suits Your Home?
Perhaps you have an existing fireplace that could be turned into an efficient heating source with an insert. Or maybe you have lots of firewood and plenty of space next to your HVAC for a furnace. Think about where you want to prioritize the heat in your home.
- Couple enjoying wood stove
Except for the furnace, most of the other categories don't have the advantage of using the ducting to distribute warm air to your home. Ideally, you should select a location that makes the best use of the heat they emit. This could be in a particularly cold section of the house, or in a centrally-located place where the heat can disperse evenly.
Where Will The Venting Go?
Because all of these appliances are wood-burning, they all require some sort of venting system. This impacts the location of the stove or fireplace because you need to consider how to run the vent pipe vertically through your home. This is simple in the case of a fireplace insert since you can use the existing chimney.
What Are The Additional Costs?
Sure you can look at the price tags for different models, but you also need to weigh the cost of installation. This includes the installation location since major remodeling or making way for the vent pipe can get expensive.
What Is Your Ideal Heat Output?
This is a case where bigger is not always better. If the heat output far exceeds your needs, you'll be uncomfortably warm when you fire it up. Thankfully appliances are rated with how much heat they produce. You can read up on this heat output (measured in BTUs) for more information about how to calculate what you'll need. Doing a little homework will keep your undersized heater from working itself to death or needing to open windows in December to cool off the house.
What Are Your Heating Efficiency Preferences?
The stoves, inserts, and closed combustion fireplaces are all far more efficient than a standard open fireplace. More efficient appliances equal less air pollution and longer-lasting fuel. However, there are some trade-offs as you get more and more efficient. For example, catalytic stoves burn cleaner than non-catalytic models but are less effective when it comes to heating larger spaces. We'll cover more on the difference between catalytic and non-catalytic later on.
What Are Your Options For Materials?
This section will focus on the different options for wood-burning stoves. The main choices are plate steel, cast iron, and soapstone. In addition to how they suit your style, these different materials have pros and cons with regard to durability, function, and cost.
- Plate steel is relatively inexpensive and allows heat to radiate to the room more quickly than cast iron or soapstone. On the flip side, it also cools down quickly, so it will not continue to radiate heat after the fire is extinguished. They are also more susceptible to cracking if the stove is overfired.
- Plate steel portable wood stove
- Cast iron has a classic look and is more durable than the plate steel stoves. It takes longer to heat up, but once it does, it will continue to radiate heat even when the fire is out. Some drawbacks are that cast iron models are becoming more difficult to find and the heavy material may make installation more of a challenge.
- Cast iron wood stove
- Soapstone stoves have a uniquely beautiful look. They usually feature a cast-iron chassis with soapstone on the outside and sometimes even lining the firebox. The stone does not get as hot as cast iron or steel and provides more gentle heat to the room. In general, soapstone is the most expensive stove material. It is also quite heavy and relatively fragile.
- Soapstone wood stove
How Are Catalytic and Non-Catalytic Stoves Different?
Catalytic stoves were developed to help facilitate a cleaner burn. However, there are also non-catalytic wood stoves that meet the EPA emissions standards. Both are effective, so which is better? Here's a quick overview of how they work and the pros and cons of both systems.
Non-catalytic wood heaters rely on a combustion chamber that has air injection tubes, as well as a set of baffles to prevent the premature escape of pollution. The system is set up so that only a small space is open to the venting collar of the stove, with the rest being covered by the baffles or bricks.
- Air injection tubes on a wood stove
The air injection tubes are usually mounted in the ceiling of the firebox, pushing the heavy particles down into the flames to be burned again. The resulting motion creates a circulating effect, burning and burning the particulates until only the lightest material can pass out the venting system. The design of this system not only cuts down on particulate pollution but also ensures that stoves reach a higher efficiency level.
- Low maintenance. The specific parts like the air tubes and baffles last for years and are cheap to replace.
- Hotter burn. This makes it easier to heat a larger area.
- No catalyst bypass. Only the air controls need to be adjusted during the start-up of the stove.
- More difficult to start. These stoves require a higher ignition temperature, so you may need the practice to get the fuel balance right.
- Not as clean-burning as catalytic models. Non-catalytic usually emit 1 to 2 grams more particulate matter.
Catalytic stoves don't have baffles. Instead, they use a catalytic combustor to help ignite the particles. Catalytic combustors have a metal coating that interacts with the escaping particles and causes them to burn at a lower temperature. Most models also have some sort of recirculation system.
- Woodstove catalyst
Since the catalyst has to be hot in order to work, most stoves have a bypass that allows the gases to go up the flue. When the catalyst is heated, this bypass closes and the flue gases start going through the catalyst instead. Non-catalytic models can also operate at much lower temperatures.
- Easier to start. They don't require the high temperatures of non-catalytic stoves.
- Cleaner burning than non-catalytic models.
- Longer, slower burn time. The lower temperatures result in a slower burn.
- Require replacement parts more frequently. Catalysts need to be replaced more frequently.
- Not as effective at heating larger areas
- Fewer selections. There are more non-catalytic models available.
There are several products to help you maximize your wood-burning heater's performance. Fans or blowers help move the hot air from the fire out into the room. Heat distribution kits offer another option for directing the hot air into other parts of the home.
Depending on your model, you may also have the option of air intake or combustion air kits. These supply the fireplace with outside air instead of relying on room air.
- Woodstove board
Stove boards and heat shields are important components for keeping your walls and floors protected and fireproof.
In addition to accessories for your heater, there are also products to help you make the most of your wood fuel. Moisture meters help you determine if your wood is dry enough to burn, and log splitters make chopping firewood much easier.
Not surprisingly, the installation requirements vary depending on what type of wood-burning heater you choose. It is critical to read and follow all of the manufacturer's instructions for installation and clearances. For safety and best results, we recommend hiring a professional installer.
The first part of the installation is the planning phase. This includes mapping out where the vent pipe will travel. Make sure it maintains the proper clearance from combustible material along the entire length of the pipe.
It is also important to make sure you have the proper clearances, stove board, or shields for the stove itself. If you are routing the pipe through an existing chimney, there are parts that help seal the empty space between the pipe and the inside of the chimney.
Wood-burning furnaces can be stand-alone units or work together with a gas furnace. (Note that in Canada, only a stand-alone installation is permitted.) A stand-alone furnace works by heating the air and distributing it throughout the home via a ductwork system. It is similar to a typical HVAC system, except that the air is heated by a wood stove enclosed in a metal cabinet.
- Furnace installation
In a tandem installation, the wood furnace is installed alongside an existing gas furnace. The ducts are arranged so that the heated air from the stove mixes with the heated air from the gas furnace. In this way, it works as supplemental heat to help lower your gas bill. You can even switch the gas heater off and run the wood furnace on its own.
Wood Fireplace Insert
In order to install a fireplace insert, you much have an existing masonry fireplace that is compatible with an insert. Most fireplace insert manufactures will have instructions for measuring your existing fireplace to find the right size insert. These measurements include the front width and height, the back width and height, and the depth of the fireplace.
Most masonry fireplaces are tapered toward the back and not completely square. This is why it is important to use all of the measurements to make sure that your insert will fit properly.
Inserts come with a frame called a surround that helps cover the gap between the insert and the edge of the fireplace. They may also require a flexible chimney liner to create the proper flue size for the insert.
- Woodstove insert
As always, read all of the manufacturer's instructions and be sure to check with your local codes and HOA before installing a wood-burning insert.
Care and Maintenance
One of the biggest rules when it comes to caring for your wood-burning appliance is to use the right fuel. The owner's manual should contain specific wood fuel recommendations for your unit. In general, use dry cordwood and never burn trash or plastic. Also, never burn painted or chemically treated wood, since the fumes can be toxic.
The other tips revolve around following the instructions for cleaning and inspections. Again, the owner's manual should have more specific information for your model. There are various tools for cleaning ash out of the chimney. You can also use a chimney-cleaning log to help make the work easier. These logs are specially formulated to react with the creosote and make it easier to remove. Also, don't forget to clean the ash out from the firebox regularly.
Once a year, schedule a professional inspection and chimney sweep to make sure your wood-burning heater is in top shape. This is important for safety, but it can also help save money since problems are caught before extensive damage occurs.
How Long Does a Wood Stove Last?
If properly cared for, a wood stove can last around 50 years. That is an excellent lifespan, but the major factor for longevity is proper maintenance. Without the right maintenance, your stove may only last 4 to 5 years.
One of the keys to extending the lifespan is to be very careful never to overfire the stove. Overfiring is when too much fuel is added and the fire becomes too hot. This could cause the stove to warp and be ruined.
- Over firing a wood stove
The vast majority of wood-burning heaters are far too large and heavy to ship via normal parcel post. Instead, they will ship by LTL freight. The freight company will call you to schedule the delivery so that you can be there in person.
Make sure you inspect the shipment right away before signing off on the delivery. If anything is damaged or missing, contact the manufacturer to resolve the issue.
Wood heaters are a simple way to bring cost-effective heat to your home. The many designs also add a cozy aesthetic and provide an atmosphere as well as warmth. If you're looking for ways to heat your home with wood, you have a number of options.
- A mother reading to her son in front of a fireplace
Hopefully, this article has given you a starting point for narrowing down which type of wood heater works best for you. And as always, please reach out to our NFI Certified Specialists if you have any questions about wood-burning heaters. We are happy to help!
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