When looking at wood-burning stoves, you will find both catalytic and non-catalytic models.
Catalytic stoves usually cost 30-40% more than their non-catalytic counterparts, but you get a more efficient appliance in return.
The critical difference is that catalytic stoves burn off ash and smoke before it escapes up the flue, using it as a secondary heat source. This enables them to produce more heat with less wood and reduce smoke emissions.
However, the absence of a catalytic device does not make non-catalytic stoves a poorer cousin.
Not only are non-catalytic stoves cheaper and simpler, but they are better suited to lower heat demands due to a shorter burn time.
Non-Catalytic Wood Stoves Explained
Non-catalytic stoves provide heat with regular combustion. The process is simple – build a fire, light it, and feed it with fuel and air.
Inside the chamber, primary air enters with an adjustable flow rate via the vents, which control how quickly the fuel burns and heat output. You keep the fire going by feeding it logs, and the fire is sustained for long as the wood lasts.
Due to the higher temperature and the lack of secondary combustion (the process of burning off waste gases to produce more heat and reduce emissions), the burn time in a non-catalytic stove is significantly less than one with a catalyst.
A non-catalytic stove is therefore a good option for those that use their stove intermittently or as a supplemental source of heat in the home.
You simply don't require the catalytic technology that increases burn time. However, you may like the idea of the increased efficiency (who doesn't?) that a catalytic model offers. But, this all comes at a significant increase in price.
Catalytic Wood Stoves Explained
A catalytic stove also uses regular combustion, but it has a catalytic converter that traps smoke. A chemical coating inside the converter interacts with the smoke and ignites it at around 500°F, using it as a secondary heat source.
The catalyst lets the fire burn at a lower temperature without smoldering, extending the burn time to more than a day and as many as forty hours.
Because the catalyst burns off ash and smoke, it also reduces emissions and creosote, a tar-like substance that coats the flue inside.
Catalytic stoves are best for continuous heating as a primary heat source. However, they have a steeper learning curve and higher maintenance costs. Maintaining or replacing the catalytic combustion plate is a common issue with these types of stoves.
They also have the benefit of reducing gas emissions, since they are burnt off instead of being released up the flue.
Catalytic and Non-Catalytic Wood Burning Stoves Compared
For a meaningful comparison, let's see how these two types of stove fare in the key areas.
Catalytic stoves are built to slow down burn times with the secondary combustion of smoke, ash, and particulates. This makes them more efficient than non-catalytic stoves, with the best stoves being 85-90% efficient.
Non-catalytic stoves burn through fuel much faster and have an efficiency rating north of 70% but rarely above 80%.
What do these percentages mean? They mean that X percentage of the heat produced heats the room.
For example, if a stove is 70% efficient, 70% of the heat heats the space, and 30% is wasted (up the chimney).
The EPA (Environmental Protection Authority) requires non-catalytic stoves to release a maximum of 7.5 grams of smoke per hour and 4.1 grams per hour for catalytic stoves. Based on EPA guidelines, this means catalytic stoves are 58% more efficient.
You can expect to pay 30-40% more for a catalytic stove of equal heating power, meaning a $2,500 non-catalytic stove might be $3,500 with a catalyst.
However, some of the most efficient catalytic stoves are more than two or three times the price, especially those from luxury brands.
Non-catalytic stoves offer the best bang for your buck at the point of purchase, but depending on how you use the stove, it might be much more expensive to run.
Non-catalytic stoves use significantly more fuel over the same timeframe as catalytic stoves, but running costs are relative.
For example, you are unlikely to run a non-catalytic stove for 24 hours – you will probably use it for 3-4 hours per day. This brings running costs in line with catalytic stoves, which can burn the same quantity of wood over 24 hours.
The bottom line – catalytic and non-catalytic stoves cost the same to run, providing that you use them correctly. If you use your non-catalytic stove over the same period, expect to burn a lot more wood, increasing your running costs.
The most significant advantage of non-catalytic stoves is they do not have an expensive catalytic converter to go bang. All you do is clean out the firebox and get the flue cleaned after a season of heavy use, and you are good to go.
Catalytic stoves require periodic vacuuming to remove dust/creosote from the combustor plate, usually weekly or every two weeks. The plate is also a serviceable part and can need replacing after only a few years of use.
Catalytic stoves need preheating before closing the damper, and it takes time to get the most out of the combustion process. The catalyst needs preheating to burn off all the smoke from combustion as early as possible.
Playing with the bypass and air controls is crucial to getting the best fire, as is monitoring the temperature, so it doesn’t get too hot.
Non-catalytic stoves are much easier to learn and use – you build a fire, light it, and let it do its thing, adjusting the air vents to change the fire ferocity.
Do I need a Catalytic or Non-Catalytic Wood Stove?
Whether you need a catalytic or non-catalytic stove mostly depends on whether you need a primary or secondary heating appliance.
Catalytic stoves provide heat output over a shorter period than non-catalytic stoves, making them better suited for secondary heating.
Non-catalytic stoves can extend burn times to over a day with fewer emissions, making them a fantastic option as a primary heating appliance.
Catalytic stoves are also cheaper, easier to maintain, and simpler to use. There is also no risk of replacing an expensive catalytic converter.
However, if ultimate efficiency and eco-friendliness are your primary goals, you can’t beat a catalytic stove.
They use significantly less fuel over a day and can eliminate the need for central heating and generators with the right heating power.