If you’ve ever wondered what, exactly, happens inside a Greenwood boiler, allow us to walk you through our patented CrossFire™ combustion system that makes possible this incredible super-efficient heating source.

The key to the CrossFire™ system is the second combustion. Humans have harnessed the power of the first combustion for thousands of years—everyone, even children, know that when you burn a log, it gives off heat. Until recently, no one took it much farther than that, which is why wood-burning stoves were so wasteful—they were wasting the opportunity of the second combustion.

When wood burns, much of the organic material is carried upward in a gray gaseous form, commonly known as smoke. When you burn wood in a chimney, this smoke condenses again when it hits the cooler air away from the fire. This condensed smoke is called creosote, and contains about 50% of the possible energy from the wood. As most chimney owners know, if creosote builds up in your chimney, it can pose a serious risk to your home, as at very high temperatures creosote can combust, causing a chimney fire that could lead to a house fire.

The brilliance of CrossFire™ combustion is that it takes the danger of creosote build up and turns it into an opportunity. After the gasses separate from the burning wood, over-fire aird is added in what’s known as the “crossfire zone” of your stove, raising the temperature by adding oxygen and completing the second combustion in the “burn-out zone,” where temperatures can be as high as 2000 degrees Fahrenheit. Heat is then transferred to the water-tube exchanger, heating the water that then heats your home.

This model improves on older models, which used downdraft technology rather than pushing the air upward and out. This downdraft technology would cause bad smells and looked dirty. With CrossFire™upward combustion, you can enjoy the beauty of your fire without the smell or mess and at a greater level of efficiency.

This video demonstrates the beauty of the CrossFire™ Combustion: