JUCA Advanced Design Woodburners

Many customers know a lot about normal woodstoves. JUCA products are so advanced and unique that there are many differences from other products you may know about. Here are some comments on unusual aspects of the JUCAs.


Normal high-efficiency (40% in actual use) stoves are so called "air-tight." This design of operation suffocates the fire to control it and therefore causes incomplete burning. This is wasteful of energy (up to 1/3 of all the energy in the wood is unburnt and goes up the chimney) and causes some serious safety hazards. Carbon monoxide is produced by air-tights in large quantities which could cause danger if the chimney ever has a leak. Creosote is present in the smoke in huge quantities due to the incomplete burning. If cooled below 350°F or so this stuff will condense in the chimney and accumulate there.

If it ever later catches fire, it burns ferociously enough to possibly damage the chimney or the house itself. JUCA products are non air-tight. Our fires burn very completely and cleanly. JUCAs get much higher combustion efficiency this way. Reports from users and our testing suggests that the non air-tight operation of a JUCA produces only one-tenth to one-fifteenth the creosote of an air-tight product comparably used.


The arrangement of the surfaces inside a JUCA is the heart of its efficiency. The technology of gas/oil furnaces and of coal/coke burning industrial boilers has been applied to a wood-fired device. The result is a heat transfer efficiency unmatched in any other wood-burner on the market. Actually, it would be very unsafe for an air-tight product to have an efficient heat exchanger. If it did then all of that massive creosote in the smoke would certainly condense in the chimney.

It is actually necessary for air-tight stoves to have somewhat INEFFICIENT heat exchangers so as not to cool the smoke too much. Our NON air-tight design doesn't have much creosote in the smoke so we can safely extract a lot of heat. Even when the smoke is cooled below the creosote condensing temperatures, little accumulates because little was in the smoke to condense. We used a computer to help design the JUCAs heat exchangers for absolute optimum performance.

Advanced aerodynamics and thermodynamics technologies were used and each part of the exchange system was independently designed for the maximum benefit for the assembly. You can certainly see why our JUCA, with more complete burning (higher combustion efficiency) and better heat exchange (higher transfer efficiency), has much better overall performance than any air-tight can safely have. If you have seen one in operation then you already know that there is a remarkable difference - the JUCA is very noticeably better.


Air-tight products have to resort to a catalytic converter or secondary combustion system to deal with the problem (created by the air-tight operation) of the massive creosote in the smoke. Since in a JUCA smoke leaves the area of the fire with very little creosote the problem doesn't even exist. Ours is the better answer.


Conventional woodstoves generate heat that rises directly to the ceiling. Cold drafts occur at floor level. There could be as much as 60 degrees difference between the floor and ceiling. Corners and other rooms are not heated. A JUCA sends the heat along the FLOOR warming it up, spreading heat to corners and other rooms. The warm air rises to make surprisingly even heat throughout the heated area. Most JUCAs also have the capability of joining a ducting system to send heat to distant parts of the house as well.

Some competing products offer forced air systems with a small capacity blower (seldom as large as 400 cfm) which is optional at extra cost. The JUCA comes standard with a good sized (465 cfm) blower with optional choices available up to 2500 cfm. So called add-on furnaces often only give an output duct size of 6 or 8" diameter. JUCAs have a generous 8 x 16" rectangular outlet to ensure being able to send enough air to fully heat the whole house.

The end result is an overall evenness of house temperature and a comfort level that is often better than that from a gas furnace. The unique JUCA operating principle allows this level of comfort previously unheard of in wood-fueled heating. Even the fact that our units are designed for large unsplit wood has nice consequences. When you use 8" diameter logs, it is easy to keep a fire overnight. Most experienced JUCA owners are so spoiled about this that they are disappointed if they wake up to a house that is not right at 70°F.


Our units are meant to be able to be installed in the living area. Glass areas and modern design help fit in anywhere. At the same time it operates as a warm air furnace at high efficiency. All this - and it uses wood like an efficient woodstove. Even though Franklin stoves are described as fireplace/stoves, they are rather inefficient when you enjoy the fire so you have to choose fireplace OR stove. A JUCA gives you both at once.

Any other add-on furnace is ugly and has to be installed in the basement. A JUCA can be installed downstairs as a conventional furnace, or as an add-on, or it can be installed upstairs in the living area and still be able to send the heat to a duct system downstairs. Of course, it can be operated as a free-standing woodstove as well. Sometimes people initially install it without ducts. Then at a later date they may install ductwork.


The outer shell of our units generally runs too cool for cooking. One family in Indiana we know of actually kept a candle on the unit all winter while it heated their entire home. From the comments on this and other JUCA info sheets, you already know the safety advantages over air-tight products. The construction of JUCAs also is safety oriented.

Numerous internal features ensure a long and useful lifetime. Even our popular B-3B weighs in at 495 lbs, so they are built to last. We use high quality high temperature glass, and a removable metal glass-shield. If you're away from home or in bed and your logs shift around, this panel makes extra sure that nothing unplanned could possibly happen.


Sometimes potential customers wonder why they haven't seen our products heavily promoted in magazines, etc. They think "If this product is as good as it seems, why don't they push it more?" Well, that has to do with our attitude toward such things. We would rather concentrate on making fine products. We choose not to hard sell. We much prefer to let our products sell themselves, as they do when they're seen at a friend or neighbor's. Then anyone can make up their own minds.

The bulk of our sales are these "word-of-mouth" sales. Virtually every dealer that we have ever had originally owned a JUCA and had to ask us to become a dealer. We like truth and accuracy about our products, and we encourage such in anyone representing JUCA. You won't often see ads for our products either, and when you do they won't be flashy - just honest and accurate. In over twenty years of offering these units, we have always been proud of what we are doing - helping our fellow man deal with one of life's many problems. We intend to continue the same tradition.

The JUCA Home Page is at: juca