Harvia 36 Duo Wood Burning Stove - WKPR36DUOS

Harvia 36 Duo Wood Burning Stove - WKPR36DUOS

The 36 Duo is an essential 2-in-1 wood-burning stove designed to heat two rooms, creating a traditional sauna atmosphere rich in steam while allowing you to relax in the adjoining fireplace room during breaks. With a large, stylish steel-framed glass door, this impressive heater is framed in durable stainless steel, making it suitable for large saunas up to 1,271 cubic feet. Enjoy the seamless transition between rejuvenating sauna sessions and cozy relaxation, all in one elegant setup.

What our Experts Think

• Heavy-duty high output (31 kW class performance)
  The WKPR36DUOS is considered a premium large-capacity wood-burning sauna stove designed for sauna rooms approx. 14–36 m³, delivering fast heat-up and strong, stable temperatures even in demanding use.
• True 2-in-1 sauna + fireplace experience (DUO design)
  Experts highlight its standout feature: it heats the sauna while also acting as a fireplace in an adjacent room, adding comfort, ambiance, and flexible living space use.
• Strong steam quality with large stone mass (~60 kg / 132 lbs)
  The high stone capacity ensures soft, long-lasting löyly (steam) with smoother heat distribution—ideal for traditional sauna enthusiasts who value consistent humidity and heat.
• Outside loading for cleaner sauna experience
  Wood can be loaded from outside the sauna, keeping the interior cleaner, reducing smoke exposure, and improving user comfort during operation.
• Efficient heat performance for large groups
  Built to maintain heat stability even with frequent door opening or multiple users, making it suitable for family saunas, cabins, and light commercial use.
• Durable Finnish steel construction
  Stainless steel outer casing + reinforced firebox structure provides long service life under repeated high-temperature wood firing cycles.
• Comfort-focused design details
  Large glass door creates visible flames, enhancing ambiance, while adjustable feet simplify installation and leveling in custom sauna builds.
• Best suited for premium sauna builds
  Experts recommend it for users who want a powerful heater + fireplace hybrid, maximum heat capacity, and an authentic wood-fired sauna experience in one system.

Q&A

Q: What is the Harvia 36 Duo used for?
A: It is a powerful wood-burning sauna stove designed for large sauna rooms, offering both strong heating performance and a fireplace-style viewing experience.

Q: What makes the “Duo” design special?
A: It has a dual-purpose structure that allows the firebox to face an adjacent room, so you can heat the sauna while also enjoying a fireplace atmosphere outside the sauna.

Q: What sauna size is it suitable for?
A: It is designed for large sauna rooms approximately 14–36 m³ (494–1271 ft³) depending on insulation and layout.

Q: What is its heating power?
A: It delivers around 31 kW of wood-burning heat output, making it suitable for fast heating of large sauna spaces.

Q: What are its key performance features?
A: It offers a large stone capacity for strong steam (löyly), fast heat-up time, and long-lasting heat retention for extended sauna sessions.

Q: Can it heat more than one room?
A: Yes, the DUO design allows heat and flame visibility in an adjacent room while still effectively heating the sauna.

Q: What materials is it made from?
A: It features a durable steel body with a stainless-steel outer casing and a large glass door for fire viewing.

Q: Does it require a chimney and professional installation?
A: Yes, it requires a proper chimney system and professional installation to ensure safe and efficient operation.

Maintenance Tips

• Remove ash after every use: Keeps airflow strong and ensures efficient, clean burning performance.
• Use only dry, seasoned firewood: Reduces soot buildup, improves heat output, and protects the firebox.
• Chimney cleaning (critical): Inspect and clean flue regularly to prevent creosote buildup and maintain safe draft.
• Stone inspection & replacement: Check sauna stones yearly; replace cracked ones and keep loose stacking for proper airflow and steam quality.
• Maintain DUO air system: Ensure firebox air intake and external feeding channel stay clear for stable combustion and clean operation.
• Exterior care: Wipe stainless steel body to prevent soot stains and maintain corrosion resistance.
• Avoid overfiring: Do not overload wood—excess heat can damage internal structure and reduce lifespan.
• Safety clearance checks: Regularly ensure required distances from walls/ceiling are maintained for safe operation.
• Annual professional inspection: Check chimney connection, firebox condition, and overall structural safety