Harvia Pro 20 SL Wood-Burning Sauna Stove
Best wood-burning heater for those wanting dual-room ambiance and authentic steam.
Embrace authentic Finnish sauna culture with the Harvia Pro 20 SL wood-burning stove. Designed for small to medium saunas, this robust heater delivers exceptional steam and a traditional wood-fired ambiance. Its unique exterior feed allows you to enjoy the mesmerizing flames from an adjacent room, doubling as a cozy fireplace. Crafted with quality and durability, the Pro 20 SL provides a powerful 24.1kW heat output, ensuring a deeply relaxing and invigorating sauna experience. It is designed for floor installation and requires 88 lbs of sauna stones for optimal performance.
$1400.00
Owner Satisfaction
4.5
/ 5
Category Rank
101
/ 162
#101 in Sauna Heaters
Price vs Category Average
-40%
Below average
Heating Power Rating
24.1
/ KW
Who it's for
- Sauna owners prioritizing a clean and debris-free interior space
- Users seeking a durable heater built for long-term reliability
- Efficiency-minded bathers wanting rapid heating with minimal wood consumption
Who should skip it
- Homeowners preferring low-maintenance heating solutions over manual cleaning
- People with limited floor space or tight sauna layouts
- Bathers who prefer the convenience of automated temperature control
Performance breakdown
Steam Quality
Generates a thick, traditional löyly that defines the authentic Finnish experience.
Heating Efficiency
Powerful 24.1kW output ensures rapid temperature rise for medium-sized sauna rooms.
Dual-Room Utility
Exterior feed design effectively bridges sauna heat with cozy fireplace ambiance.
Build Durability
Robust construction and cast-iron framing promise years of reliable, heavy-duty service.
Stone Capacity
Large stone reservoir provides consistent heat retention and smooth steam release.
Operational Ease
Mechanical controls are straightforward, though wood-burning requires active manual maintenance.
Key Specs
Heating Power Rating
24.1 KW
Mounting Type
Floor Standing
Stone Capacity
88.0 lbs
Height
30.0 inches
Steam Generation Capability
True
Warranty
2 years limited
Control Type
Built-in Mechanical
Power Source Type
Wood Burning
Features
- Authentic wood-burning sauna experience
- View fire from adjacent room
- Excellent steam generation (Löyly)
- Heats two rooms simultaneously
- Finnish engineering and quality
- Cast-iron framed glass door
- Exterior feed convenience
- Designed for small to medium saunas
What customers say
Customers highly value the Harvia Pro 20 SL for its superior quality and authentic heating performance. The stove consistently delivers powerful yet comfortable steam, creating an ideal sauna atmosphere. A key feature praised is the external wood feeding tunnel, which greatly improves convenience by keeping the interior clean and minimizing smoke interruptions. Reviewers confirm the unit heats spaces rapidly and maintains temperature efficiently using less wood. Built with heavy-duty steel, this stove is recognized as a durable, long-term investment. While the initial price is premium, the combination of exceptional longevity, reliable output, and enhanced user convenience justifies the cost for serious sauna enthusiasts.
Know before you buy
The 'SL' stands for 'side-loaded' or 'exterior feed.' This design allows you to load wood and view the fire from an adjacent room, effectively serving as both a sauna heater and a fireplace.
This unit requires 88 lbs of sauna stones. Using the correct amount of stones is essential for consistent heat retention and the quality of the steam, or 'löyly,' produced.
The Pro 20 SL is specifically engineered for small to medium-sized saunas. With a 24.1 kW output, it is powerful, but you should verify your sauna's cubic volume against the manufacturer's heating capacity guidelines to ensure it is the right fit for your space.
No, the Harvia Pro 20 SL features built-in mechanical controls. This makes the operation straightforward and eliminates the need for complex electrical wiring for a control interface.
You will need to regularly remove ash from the firebox and inspect the chimney flue for creosote buildup. Additionally, you should periodically check your sauna stones for cracking or crumbling and replace them to maintain optimal airflow and heat efficiency.
While the unit is floor-standing, wood-burning sauna stoves require precise installation, including proper clearance from combustible materials and a correctly sized chimney system. We strongly recommend having a professional installer or local building inspector verify your setup to ensure safety and compliance with local fire codes.
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