Harvia Pro 20 SL Wood Burning Sauna Stove with Firebox Extension - WKPR20SLM

Harvia Pro 20 SL Wood Burning Sauna Stove with Firebox Extension - WKPR20SLM

Are you passionate about wellness and self-care? If you appreciate the soothing benefits of saunas and enjoy nourishing meals, hiking, yoga, and meditation, the  with Firebox Extension is the ideal addition to your wellness sanctuary. This high-performance stove offers effortless purchasing and installation, providing robust, consistent heat, while the firebox extension allows for convenient refueling from an adjacent room, ensuring an uninterrupted sauna experience. As a trusted brand known for innovative designs, represents quality at My Sauna World, making this stove a valuable investment backed by decades of expertise. Join a global community of wellness enthusiasts and enjoy the transformative benefits of regular sauna use, enhancing your overall well-being with improved muscle recovery, stress reduction, and better sleep.

What our Experts Think

• High-performance heating for medium saunas (8–20 m³)
  Widely regarded as a strong, professional-grade wood-burning stove designed for consistent heat output and reliable steam quality in small to mid-sized sauna rooms.
• “Through-the-wall” convenience design
  Experts highlight the SL (side-loading) firebox extension as a major advantage—allowing wood to be fed from outside the sauna, keeping the bathing area cleaner and more comfortable.
• Excellent steam (löyly) quality
  Large stone capacity (~40 kg) helps produce soft, even, long-lasting steam rather than harsh bursts—ideal for traditional sauna experience.
• Built for durability & safety
  Heavy-duty steel construction, cast-iron glass door, and CE-certified design make it suitable for regular and long-term use in demanding conditions.
• Trusted Finnish engineering standard
  Frequently praised by sauna installers and users as a “no-nonsense” reliable Pro-series heater with simple operation and low maintenance requirements.
• Best for authentic sauna experience
  Experts consistently recommend it for users who value real wood-fired heat, natural ambiance, and strong heat retention over modern electric alternatives.

Q&A

Q: What is the Harvia Pro 20 SL used for?
A: It is a wood-burning sauna stove designed to heat small to medium-sized saunas while also providing a cozy fireplace effect in an adjacent room.

Q: What does the “SL” (through-the-wall firebox) feature do?
A: It allows firewood to be loaded from outside the sauna room, so you can heat the sauna without bringing wood inside.

Q: What size sauna is it suitable for?
A: It is ideal for sauna rooms approximately 8–20 m³ (about 283–706 ft³), depending on insulation and design.

Q: Is it suitable for residential use?
A: Yes, it is designed for home and cottage sauna use, offering efficient and authentic wood-fired heating.

Q: What are its main performance features?
A: It provides strong heat output, excellent steam (löyly), and a large stone capacity for steady, even heat distribution.

Q: Does it support a fireplace-style viewing experience?
A: Yes, it features a glass door so you can enjoy the visible flame while the sauna heats up.

Q: What makes it different from standard sauna stoves?
A: The through-the-wall firebox extension separates wood feeding from the sauna space, improving convenience and cleanliness.

Q: Does it require professional installation?
A: Yes, professional installation is strongly recommended due to ventilation, clearance, and chimney safety requirements.

Maintenance Tips

• Empty ash box regularly: Clean before each use to ensure proper airflow and protect the fire grate.
• Use only dry wood: Seasoned wood burns cleaner, improves efficiency, and reduces soot buildup.
• Clean chimney & flue: Remove soot and creosote buildup regularly to maintain safe draft and prevent fire risk.
• Inspect sauna stones: Re-stack and replace cracked stones at least once a year for proper heat and steam performance.
• Remove ash safely: Store ash in a metal container away from flammable materials (may contain hot embers).
• Wipe exterior surfaces: Clean dust and residue with a damp cloth to prevent corrosion and maintain finish.
• Avoid overheating: Do not overload wood; excessive firing reduces stove lifespan and safety.