Cf900 92% 7 22

CleanFire Outdoor Wood Furnaces

The most efficient furnaces deliver the best value. At 92% overall efficiency (LHV), the CleanFire 900 provides the highest efficiency of EPA Certified stick-wood burning appliances compared to outdoor appliances with a maximum output greater than 300,000 Btu/hr.* It also delivers the highest Btu rating of cord wood appliances, with a rating of 400,000 Btu/hr. CleanFire furnaces are among the top for efficiency of all stick-cord wood heating appliances certified for sale for residential heating in the USA.

*EPA cord wood Hydronic Heater list 7/28/2022.

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The CleanFire that’s right for you:

EPA Step 2 Certified Outdoor Wood Furnaces
Titanium Stainless Steel Firebox

Cleanfire 300 Sq Nologo icon

CleanFire 300

Mfr’s Rated Heat Output Capacity:
150,000 Btu/hr
Firebox Volume:
10 cubic ft.
Water Capacity:
150 gal.

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Cleanfire 500 Sq Nologo icon

CleanFire 500

Mfr’s Rated Heat Output Capacity:
200,000 Btu/hr
Firebox Volume:
14 cubic ft.
Water Capacity:
205 gal.

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Cleanfire 700 Sq Nologo icon

CleanFire 700

Mfr’s Rated Heat Output Capacity:
245,000 Btu/hr
Firebox Volume:
23 cubic ft.
Water Capacity:
330 gal.

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Cleanfire 900 Sq Nologo icon

CleanFire 900

Mfr’s Rated Heat Output Capacity:
400,000 Btu/hr
Firebox Volume:
32 cubic ft.
Water Capacity:
420 gal.

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CleanFire checks every box of what an outdoor furnace should be

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Clean & Efficient

Enjoy the benefits of cleaner burning and high efficiency and use up to 60% less wood compared to many other forms of wood heating.

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Easy Maintenance

The patented vertical Easy View Heat Exchanger with hinged door provides full access without the use of tools. Fully accessible front area and rear ash cleaning area.

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The Firestar combustion controller constantly monitors how the wood is burning and adds air where and when it’s needed for the cleanest, most efficient combustion. You can even see how it’s operating in real time on your smartphone.

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Comfortable & Safe

CleanFire outdoor wood furnaces provide the warmth and comfort of burning wood – without the mess, inconvenience and dangers that can be caused by indoor burning.

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Eliminate Heat Bills

Drastically reduce or eliminate your fossil fuel or electric heating bill. Owners that cut their own wood can entirely eliminate their heating bills.

How the CleanFire Works

CleanFire Design Comparison

Learn more about how an outdoor furnace works by visiting our How It Works page.

EPA Step 2 Certified Outdoor Wood Furnaces

Wm Firestar Photo B


Heating with wood can’t be easier than this. The FireStar combustion controller constantly monitors how the wood is burning and automatically adds air where and when it’s needed for the cleanest, most efficient combustion.

  • Reserve Mode – reserves a portion of the previous wood load so you’ll never have to relight a fire
  • Burning Time Monitor – helps to estimate how much wood is left
  • Clean Reload – can eliminate smoke when you open the firebox door to add wood
  • Text Alerts – enable this feature if you want to be notified when it’s time to add wood
  • Industry Exclusive Remote Monitoring with MyFireStar.com.

The FireStar Controller with onboard Wi-Fi keeps you informed of your furnace’s performance and operation. View operational information and receive text alerts on your smartphone or computer. Watch a live demo at MyFireStar.com/demo.

MyFireStar.com DEMO
How It Works

Precise Air = Precise Burn

The proper amount of air at just the right time is imperative for the cleanest, most efficient burn. When the fire needs air (such as during startup or when burning higher moisture wood), FireStar delivers the precise amount of air needed. When less air is needed…FireStar delivers again.

How It Works

Multi Purpose Design

The CleanFire’s patented Air Charge Tube is an example of an innovative feature with multiple purposes. It keeps coals from falling into the Reaction Chamber and also directs oxygen into the Fusion Combustor. There, the oxygen mixes with the combustion gases and is forced down into the Afterburner. The Air Charge Tube also helps the furnace to relight faster. Visit the How It Works page to learn more.

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