What GreenFlame Actually Is
GreenFlame isn't a separate stove. It's Harvia's clean-burning combustion technology, and on this collection it's built into the Linear 22 body. So the heater shape, the wide front face, the room ranges — those come from the standard Linear wood-burning series. What GreenFlame adds is a redesigned firebox and air-flow path that burns the wood more completely, which means more heat out of every log and less smoke up the chimney.
Here's the short version most buyers want: if you like the modern, rectangular Linear look but you also care about burning clean and efficient — because you're in an area with wood-stove rules, or you just don't want a smoky backyard — GreenFlame is the variant to buy. Same family, cleaner burn.
Worth being precise here, because the marketing on wood stoves gets fuzzy fast. Harvia describes GreenFlame as clean-burning and efficient combustion. That's the claim we'll make and nothing beyond it. We're an authorized Harvia dealer, not the manufacturer, so we're not going to attach an emissions number or a certification to it that Harvia doesn't publish. What we can tell you is the design intent: more complete combustion, better fuel efficiency, less visible smoke than a standard wood firebox.
Why Wood-Burning at All
Most people shopping heaters default to electric, and for a lot of installs that's the right call. It's faster to heat and there's no chimney. But wood-burning has advantages electric can't touch, and GreenFlame keeps the wood experience while cleaning up its biggest downside.
First, no electrical hookup. No dedicated 240V circuit, no electrician bill for the heater itself, no breaker to trip. For a cabin, an off-grid build, or a backyard sauna where pulling a circuit is a hassle, that's the whole argument. Fire and stones.
Second, the ritual. Building the fire, the crackle, the smell, watching it through the door — that's what people picture when they think "authentic Finnish sauna." An electric heater hits the same temperature but it can't reproduce the atmosphere. GreenFlame just makes that ritual burn cleaner, which matters if your sauna sits near neighbors or you light it often.
Third, efficiency means you feed it less. A cleaner, more complete burn gets more usable heat out of each load of wood. Over a season of regular sessions, that adds up — less wood split, hauled, and stacked.
The GreenFlame Models in This Collection
Harvia Linear 22 GreenFlame (WKLI22GM), 15.7kW. The core model. It heats sauna rooms from 317 to 635 cubic feet, which covers most mid-to-large home saunas — comfortable 4–6 person indoor builds and a lot of outdoor cabins. Holds 88 lbs of stones and feeds from inside the sauna room. If you want the clean burn in the Linear silhouette and don't need a built-in water heater, the Linear 22 GreenFlame is the one.
Harvia Linear 22 GreenFlame ES (WKLI22GESM), 15.7kW with water tank. Same heater, same 317–635 cu ft range, same clean-burn combustion — but with an integrated water tank built onto the stove. The fire heats the tank as it heats the room, so you've got hot water on hand without a separate system. That's genuinely useful for an outdoor sauna with no plumbed hot water, or anywhere you want warm rinse water as part of the session. The Linear 22 GreenFlame ES is the pick when hot water near the sauna is part of the plan.
Sizing the Right GreenFlame for Your Room
Both GreenFlame models cover the same 317–635 cubic foot range — that's the published Harvia figure, and the heater performs when you stay inside it. The choice between the two isn't about room size at all. It's about the water tank: get the ES if you want heated water, get the standard 22 if you don't.
A few practical notes on whether 317–635 cu ft actually fits your build. Cold climate, lots of exterior wall, or a big glass door or window? Lean toward treating your room as larger than the raw cubic footage suggests — heat escapes faster, so you want the heater working in the middle of its range, not at the ceiling of it. Tight, well-insulated indoor room? You can sit comfortably at the upper end. If your sauna runs smaller than 317 cu ft or bigger than 635, GreenFlame isn't the right body — step over to the round Legend or Pro lines, which span a wider set of room sizes. You can compare all the Harvia wood options on our wood-burning sauna stove collection.
Chimney, Clearances, Stones, and What Else You Need
The heater on its own isn't a finished install. You'll need a chimney kit sized to the stove, plus roof flashing, lead-through insulation, and a rain cap. Clearance to combustible walls is non-negotiable on any wood-burning heater — the exact figures live on each product page's spec sheet, and you read them before you frame the room, not after. Wood stoves run hotter on their surfaces than people expect.
Stones are sold separately. Both GreenFlame models hold 88 lbs, and Harvia Olivine Diabase is the right match — pick it up from our sauna stone collection. Don't use generic landscape rock; it traps moisture and cracks, sometimes violently, under the heat cycling of a wood fire. Fill the basket to spec for the steam to behave the way the stove was designed to.
For the foundation, venting, and prep work that trips up most first-time wood-sauna builders, our sauna installation walkthrough covers what to sort out before the stove arrives. Always consult a licensed professional for any electrical work, and follow Harvia's clearance and venting requirements for the specific model — local fire code varies by jurisdiction.
GreenFlame vs. Linear vs. Legend vs. Pro
Harvia makes four wood-burning lines and people mix them up constantly. Here's how they actually sort out.
The cleanest way to think about it: the Linear is the wide, rectangular, modern-faced wood stove body. GreenFlame is the clean-burning, efficient-combustion version of that same Linear body — so GreenFlame and Linear aren't competitors, they're the same silhouette with two combustion options. The standard Linear 16 burns like a normal high-quality wood stove; the GreenFlame burns cleaner. Pick Linear if you don't need the clean-burn tech, pick GreenFlame if you do.
The Legend and Pro are different bodies entirely — round, not rectangular. The Legend is Harvia's flagship: heaviest construction, largest stone mass, the softest and longest-lasting steam if löyly quality is what you care about most. The Pro is the mid-tier workhorse — solid heat, moderate stone load, no-nonsense, priced below the Legend. Choose between the round lines and the Linear family mostly on looks and on stone mass: the wide Linear/GreenFlame body carries less stone (88 lbs) than a loaded Legend, so if maximum steam is the priority, the Legend wins; if the modern rectangular look and a clean efficient burn matter more, GreenFlame wins.
GreenFlame Heater Packages
If you'd rather not cross-reference which chimney section and which stones fit which stove, we bundle the major configurations. Our Harvia wood-burning heater packages pair the heater with a matched chimney kit and stones, usually a little cheaper than buying every piece separately — and you skip the part where you order a flue that doesn't fit.
