Why you don’t want to incorrectly operate your stove

Our Kuuma stoves are legendary for how well they are built and perform (usually for decades).  However, there is a reason why we make many efforts (verbal, videos, website, and owners manual) to explain safe operation.

Many companies wouldn’t share something like this, showing damage to their products.  Still, Lamppa Manufacturing believes in trying to help others avoid making the same mistake by educating them on how to operate most wood-burning sauna stoves correctly.  We will continue to do our best to help people understand ways to improve how they burn wood.

This stove was purchased in 2017. “There are about 80 people who use this sauna regularly. It was repeatedly overfired (ashpan open and draft wide open), and one knucklehead used a battery-powered leaf blower in the ashpan.  It averaged 12 hours of use a day (18 hours on weekends) from October through April.  Unfortunately, some people can not be taught to do anything correctly. When used correctly, I have no problem getting the hot room up to 170-180°with the throttle barely open.  Our building is 10′ X 18′, the hot room is 9.5′ X 7.5′, it has a 7′ ceiling, walls and ceiling are insulated.  The stove has had between 10,000 to 12,000 hours of hard use, something most stoves will never see.”  said Roy M

We rarely see structural damage within the first decade or even two, but when we do, 90% of the time, it’s on an external feed sauna stove.  External feed stoves can work well in specific applications, but they will always take longer to heat due to the 25% heat loss off the front of the stove that is outside of the hot room.  If you understand this and operate accordingly, they can still work great.  If you consistently try to cut corners to save a little time on the initial heating of your hot room, you will degrade the longevity of your stove.  When I say cutting corners, I mean running it with the draft wide open (only meant for the first 5-10 minutes to get the fire going) or leaving the ashpan open for more than a few minutes.  Many people who don’t understand wood burning think this is fine. Still, in reality, you are mainly losing heat up the chimney while operating the stove at temperatures it’s not meant to handle for extended periods, especially when you introduce water for steam.

We want to help everyone burn wood better, and it’s one of the main reasons why the Kuuma was initially created.   Now the Kuuma can burn nearly anything, but you can only extract the number of BTUs available in each piece of wood.  So to operate your stove optimally, we recommend using seasoned wood, having a sufficient draft, sizing your stove correctly, and not allowing it to be overfired.  We give the owner complete combustion draft control, which works great for most people.  We could restrict this, but it wouldn’t work as well.  Your car can go 150+ mph, but it sure wouldn’t last very long if driven like that consistently.

If I consistently operated it incorrectly, I could burn through one of our stoves in a few years.  However, I also know that if I burn the same stove correctly, it will last for decades.  The Kuuma wasn’t designed as a commercial sauna stove, even though it can work great for those applications. We can build an actual commercial stove for $6-$8k because of all the ultra-high temp stainless steel and how expensive it is, especially now.  Knowing how this stove was operated, I’m proud of how long it lasted because I know how quickly it would happen if you used one another type of stove like this for an extended period.

We love speaking with our customers, so if you have questions, please feel free to reach out.


Garrett Lamppa (CEO)

Lamppa MFG Inc.