All stoves that are EPA-certified have some common elements: they all use a new method to inject combustion air into the firebox. It is important to inject air at the right places to maximize combustion.
Primary Air is air for combustion. It’s controlled by the user, either by opening or closing a valve or turning a dial, or pushing an air control lever in one direction.
Removing Smoke from the kitchen is one of the crucial parts in order to enjoy a healthy kitchen. It is recommended for people to use an auto clean chimney in order to enjoy better performance. Some of the Glen Kitchen Chimneys have a reputation of offering the best options in the residential segment. Inalsa Kitchen chimneys offer the best performance in Commercial segments.
You may have noticed, if you’ve ever used a pre-EPA stove or oven, that the stove lets air in through a few specific points. This is usually through a hole with an adjustable valve. This design results in a poor distribution of air within the firebox. These older stoves are less efficient at burning fuel, particularly during low burns. Many of the combustible gases emitted from burning wood are lost up to the flue and remain unburned.
Primary air enters most stoves that are EPA-certified through a narrow, long opening at the top of each firebox. This allows for a distributed flow of air into the stove. This allows for a more efficient mixture of oxygen and fuel, which results in more efficient primary combustion.
EPA-certified stoves use a second type of burning to burn the combustible gases emitted from the fuel load. This can be done either with a non-catalytic secondary combustion air system or a catalytic couter.
How EPA-stoves achieve this second phase of combustion is what categorizes them either as catalytic or not catalytic stoves.
Some stoves that are pre-EPA certified use catalytic technology. We will be focusing on stoves that have been certified EPA-certified, which include a catalytic combustor as well as other features required to obtain EPA certification (such as a better primary combustion air design).
A catalytic combustor is used to ensure clean burning in catalytic stoves. Although this is complicated, it is worth learning.
Catalytic combustors function in the same way as catalytic converters on cars: smoke passes through the combustion chamber and is burned to create heat, not pollution.
You also get the added benefit of the wood stove catalytic units.
A catalytic combustor refers to a ceramic insert that is round, square, or rectangular and has many small channels or tubes running through it. It looks like a honeycomb. A layer of a catalyst chemical is applied to the ceramic’s surface. It is usually palladium or platinum.
The chemical coating reacts with the smoke as it passes through the channels at sufficient temperatures. This reduces the ignition temperature and causes the smoke to ignite. The chemical coating is not burnt or eaten during the process.
Some believe that the EPA requires the use of a catalytic combustor. They don’t. Stoves must pass the test and the manufacturer can come up with a design to do so.
Non-catalytic stoves, also known as non-cat stoves, maximize combustion efficiency by using secondary combustion air. This is done by injecting air (secondary) into the stove at the right places to reduce the amount of smoke and gases emitted from the fuel load.
Non-cat stoves are equipped with a set of perforated stainless steel pipes (or a perforated baffle or similar device) that run across the top of their fireboxes. These tubes spread air throughout the stove’s interior at the top to allow the gases from the fuel load to mix. This maximizes combustion.
The stove user cannot control the flow of secondary oxygen into the stove. It is preset by the stove’s design. This means that even at low burn rates (when primary air control is on low), the second phase of combustion will occur, providing clean-burning and efficient fuel use.
Which is better, Catalytic or non-catalytic?
Each has its benefits. I have one of each in my home. The catalytic stoves are more efficient and have a longer burn time than similar-sized non-cat stoves. These stoves are able to withstand long, low-burn cycles but require more maintenance. Non-cat stoves are easier to operate and have a brighter fire picture (virtually every new stove has glass doors).
Before you make a decision, read this section about Buying a New Stove. Then, talk to your stove shop’s experts.