Serving Northern St. Louis County, Minnesota

Lamppa Manufacturing- Kuuma Stoves


512 3rd St. S., Tower, MN 55790


Kuuma furnaces the cleanest on the market

Exceptional efficiency results raising the profile of Tower-based Lamppa Manufacturing


Decades of effort to design the world’s cleanest and most efficient wood furnace have paid off for Tower-based Lamppa Manufactur-ing.

Independent results by one of the world’s leading testing labs, have found that wood furnaces designed by the company burn with virtually no smoke, and with an overall efficiency of more than 86 percent— an efficiency that’s unheard of for wood furnaces of any kind.

The company recently released the results of the testing, conducted in July and August by an Intertek lab in Madison, Wis. The results have raised the profile of Lamppa Manufacturing’s two wood furnaces, the Kuuma Vapor Fire 100 and the Vapor Fire 200, which are now rated among the cleanest ever developed. New EPA guidelines, which were developed to reduce the emissions of particulates from new wood stoves, allow up to 7 grams per hour of particulates, which is a level that many wood stove manufacturers struggle to meet. Wood furnaces, which are designed to work in centralized, forced air heating systems, tend to be even dirtier and less efficient than smaller stoves, since they often burn at lower temperatures, using larger fire chambers.

Yet the latest testing shows that the Kuuma stoves are a spectacular exception, with results ranging from 1.0 to 0.45 grams of particulates per hour, depending on conditions.

“There’s no furnace in the world that does what this one does,” said Daryl Lamppa, who has run the stove manufacturer for many years, and who, along with his father Herb, is behind the design and testing of the Kuuma Vapor Fire models.

Qualified for tax credits

While Daryl and Herb have long known they had developed two remarkably clean-burning stoves, they hadn’t had them tested in more than 20 years. But the company needed the test data to qualify for a new federal tax credit, which can cut the cost of purchase of qualifying wood stoves by as much as $1,500. In order to qualify, however, stoves must show a thermal efficiency rating of 75 percent or higher, and must have particulate emissions of less than 7.5 grams per hour, or 4.5 grams for catalytic stoves. With a thermal efficiency of 84 percent, the Kuuma furnaces not only meet the standard for smaller wood stoves, they beat it by a substantial margin. And as for the particulate emissions, they are virtually unprecedented.

The efficiency of the Kuuma stoves is so high, that they likely couldn’t get much better without creating some practical difficulties. Among the typical emissions of a wood stove is water vapor. Under normal conditions, said Daryl, there’s enough heat going up the chimney that the water remains as vapor, but with the Kuuma, if the stove were any more efficient, the chimney temperature would be low enough that steam would likely condense and run back down the chimney.

The Kuuma stoves are so efficient, says Daryl, because of a patented design that truly gasifies the wood, ensuring the cleanest and most efficient burn possible. “It’s not built like an ordinary stove,” said Daryl. The patented design utilizes a series of baffles along with computerized controls, to precisely manipulate airflow. “It gasifies the logs and burns them clean,” said Daryl. “It really does burn in a different way, using a natural draft.” The gasification starts at the front of the logs and slowly works back, providing a longer burn and a more stable output temperature, according to Daryl. That allows it to produce useful heat 8-10 hours on a single filling, and to maintain hot coals for many hours after that.

Years of effort

The remarkable test results for the Kuuma stoves represent the culmination of years of experimentation by both Daryl and Herb. Both father and son followed in the footsteps of Richard Lamppa, Herb’s father, who started building sauna stoves 70 years ago. Lamppa Manufacturing still produces wood and electric sauna stoves and both types are widely sold.

The company sold their first Kuuma wood furnaces back in 1977. By 1982, they had developed the Vapor Fire line, which burned remarkably cleanly. While air emissions were not as big a concern back then, the danger from creosote build-up was, and that was the biggest factor driving their effort to improve efficiency of the burning process. “We wanted to protect homes and save lives, and make wood burning easier,” said Daryl. Testing on those early Vapor Fire stoves showed they exceeded even today’s more stringent requirements, and they produced very little creosote.

Yet neither Daryl nor Herb were content to rest on their laurels. They noted that at times, when their stoves were burning well, they produced no visible smoke—which meant no creosote— so they decided to find a way to maintain such a clean burn all the time.

Over the years, the two made countless refinements, and conducted thousands of test burns, to find just the right air mix for a near-perfect burn. Eventually, they replaced manual draft controls with a computerized version, to ensure proper airflow from start to finish, resulting in combustion efficiencies ranging from 98.1 to 99.4 percent.

Interest growing

Word of the remarkable test results has slowly gotten out, and that has already stepped up the pace for this small manufacturer and its half dozen employees, who operate in a small, dimly-lit plant on the south side of Tower. The first story on the stove appeared in the September issue of Farm Show Magazine and Daryl says the phone has been ringing steadily ever since. “And I have six guys just chomping at the bit who want to sell them,” he added.

At this point, the Lamppas have no plan to take on outside dealers, at least for now.

“We couldn’t produce fast enough to start working with dealers,” said Daryl. Still, he isn’t ruling out working with dealers in the future, and he’s thinking about possibilities for expansion. “We are interested in ramping up production down the road,” he said.