The Harvia PRO 36 is a 31kW wood-burning sauna stove for rooms from 494 to 1,271 cubic feet - the highest-output configuration in Harvia's PRO Series and the classic choice for large saunas and group bathing. The graphite black steel body with stainless steel front, top and ash box is the same Pro Series finish used across the lineup, chosen for ease of cleaning and long-term durability. The cast-iron glass hatch faces into the sauna room, filling the space with the warm glow of the fire. The door direction is reversible. The fire chamber holds 132 lbs of AC3020 stones (3 boxes, 10-15 cm, sold separately) - enough stone mass to sustain hearty steam for a large group throughout a long session, even if the fire temporarily dies down. A stainless steel air-flow spoiler improves combustion efficiency and the fire chamber and fire channels are designed by Harvia to heat the sauna quickly and burn cleanly. Adjustable feet simplify installation. Flue: 115mm (4.5") European standard - a 6" North American adapter is required and sold separately. Pallet delivery - scheduled freight appointment required. CE and EAC certified. Made in Finland by Harvia.
31kW for 494 to 1,271 cu ft - a powerful pack that will never run out of steam
Harvia describes the PRO 36 precisely: a powerful pack for large saunas that will never run out of steam. At 31kW across the 494-1,271 cu ft range, the PRO 36 is built for situations where the PRO 20's 24.1kW is not enough - a log cabin sauna at the larger end of the range, a sauna that runs for a large family or group bathing session over several hours, or an outdoor sauna in a cold climate that needs maximum output to reach and hold temperature in a big room. The generous stone load of 132 lbs works in tandem with the high output: the fire charges the stone mass rapidly, and that stored thermal energy sustains heat and steam well beyond the life of the fire. Harvia notes directly that the stone capacity makes it possible to enjoy the sauna for a long time - you will not run out of heat even if the fire temporarily goes out.
Stainless steel air-flow spoiler and efficient fire chamber design
The PRO 36 features a stainless steel air-flow spoiler that improves burn efficiency by optimising combustion airflow through the fire chamber. The fire chamber and fire channels are purpose-designed by Harvia to ensure the sauna heats up quickly and the fire burns cleanly - reducing smoke output, improving heat transfer to the stone mass, and extending fire chamber service life. The stainless steel front, top and ash box make the most frequently handled surfaces easy to clean and resistant to the heat discolouration that affects painted finishes over time. The steel upper grate provides a durable combustion platform for the firewood load. Maximum firewood length is 15.3" (390mm) with a diameter of 3" to 6" (80-150mm).
Safety clearances and WL550 protective sheath option
The PRO 36 requires 19.69" (500mm) from combustible materials on all four sides and the front - a wider clearance than the PRO 20 platform, appropriate for the higher 31kW output. To non-combustible materials, the side and back clearances reduce to 3.94" (100mm). Ceiling clearance is 4.1 ft from the top of the stove. The optional WL550 protective sheath (sold separately, specific to the PRO 36) reduces the safety distances to combustible materials to 4.7" (120mm) on all sides when installed - providing significant bench placement flexibility in rooms where the standard 19.69" clearances would constrain the layout. The optional WL110 floor plate (22"x25"x2.5") is also available for floor protection. A licensed chimney professional is recommended for all flue installations.
31kW wood-burning sauna stove for rooms from 494 to 1,271 cubic feet. PRO Series - the classic heater for large saunas and group bathing. Graphite black body with stainless steel front, top and ash box. Cast-iron glass hatch - reversible door direction. No electricity required. Stainless steel air-flow spoiler for improved combustion efficiency. 132 lbs AC3020 stones required (3 boxes, 10-15 cm, sold separately). Safety distances: 19.69" all sides and front (combustible). With WL550 sheath: reduces to 4.7" all sides. Top or back flue connection. 115mm flue - 6" adapter required for North America (sold separately). Max firewood 15.3" / 3-6" diameter. Dimensions: 20.08"W x 20.08"D x 31.89"H. Adjustable feet. Optional: WL550 protective sheath, WL110 floor plate, pipe-model water heater. Pallet delivery - scheduled freight required. 2-year warranty (consumer). CE and EAC certified. Made in Finland by Harvia.
31 kW 494 to 1,271 cu ft PRO Series - large sauna and group bathing Classic heater - highest output PRO Series Graphite black body - stainless steel front and top Cast-iron glass hatch - reversible door direction Stainless steel air-flow spoiler Wood-burning - no electricity required 132 lbs AC3020 stones required (3 boxes, 10-15 cm) Safety: 19.69" all sides and front (combustible) With WL550 sheath: reduces to 4.7" all sides Top or back flue connection 115mm flue - 6" adapter required for North America Max firewood 15.3" / 3-6" diameter 20.08"W x 20.08"D x 31.89"H Adjustable feet WL550 protective sheath compatible Pallet delivery required 2-year warranty (consumer) CE and EAC certified - made in Finland
⚠️ 132 lbs AC3020 stones (3 boxes, 10-15 cm) required - not included. 6" North American flue adapter required - not included. Pallet delivery. Stones and the 6" adapter must be purchased separately. An additional box of stones is recommended for selection of best-fitting stones. This stove ships by scheduled pallet freight - a delivery appointment is required. At 154.3 lbs net weight, plan for on-site assistance to move the stove from the pallet delivery point to its installation position. A licensed chimney professional is recommended for all flue installations.
ℹ️ PRO 36 vs PRO 20 - selecting the right PRO Series output for your room size. PRO 20 WKPR20M: 24.1kW, 283-706 cu ft - the mid-range PRO configuration for home saunas in the small to medium range. Tighter safety clearances (4" sides and back, 12" front) and lighter stone load (88 lbs, 2 boxes). PRO 36 WKPR36M (this listing): 31kW, 494-1,271 cu ft - the highest-output PRO Series stove for large sauna rooms, log cabin saunas, outdoor saunas in cold climates, and group bathing. Wider safety clearances (19.69" all sides) and larger stone load (132 lbs, 3 boxes). Both share the same graphite black finish, stainless steel front and top, cast-iron glass hatch, reversible door, 115mm flue, and WL550 protective sheath compatibility. Choose the PRO 20 for rooms up to 706 cu ft. Choose the PRO 36 for rooms from 494 to 1,271 cu ft where 31kW output and a 132-lb stone load are the right specification.
Specifications
Performance
| Power output |
31 kW |
| Fuel type |
Wood - no electricity required |
| Room volume |
494 to 1,271 cu ft (14-36 m3) |
| Stone capacity |
132.3 lbs / 60 kg (3 boxes AC3020, 10-15 cm) - sold separately |
| Stone size |
O 10-15 cm (AC3020) |
| Max firewood length |
15.3 in (390 mm) |
| Firewood diameter |
3 in to 6 in (80-150 mm) |
Safety distances (combustible materials)
| Front |
19.69 in (500 mm) |
| Left side |
19.69 in (500 mm) |
| Right side |
19.69 in (500 mm) |
| Back |
19.69 in (500 mm) |
| Ceiling clearance |
4.1 ft (1,250 mm) above heater top |
| Side / back (non-combustible) |
3.94 in (100 mm) |
| Minimum room ceiling height |
6.56 ft (2,000 mm) |
| With WL550 protective sheath |
Reduced to 4.7 in (120 mm) all sides |
Flue and installation
| Flue connection diameter |
115mm (4.5") - standard European |
| Flue connection position |
Top or back - selected during installation |
| North American adapter |
6" (155mm) adapter required - sold separately |
| Legs |
Adjustable feet |
| Delivery |
Scheduled pallet freight - appointment required |
Physical dimensions
| Width |
20.08 in (510 mm) |
| Depth |
20.08 in (510 mm) |
| Height |
31.89 in (810 mm) |
| Net weight (stove only) |
154.3 lbs (70.0 kg) |
| Gross weight (packaged) |
158.8 lbs (72.0 kg) |
Construction and finish
| Body color |
Graphite black painted steel |
| Front and top |
Stainless steel - easy to clean |
| Ash box |
Stainless steel |
| Glass hatch |
Cast-iron framed - reversible door direction |
| Upper grate |
Steel |
| Air-flow spoiler |
Stainless steel - improves combustion efficiency |
| Legs |
Adjustable feet |
| Installation |
Floor-mounted, vertical orientation |
Certifications and compliance
| Certifications |
CE / EAC certified |
| Origin |
Made in Finland by Harvia |
| Warranty |
2-year limited (consumer use) |
Optional accessories (sold separately)
| North American flue adapter |
Harvia WZ115155 (6" / 155mm) |
| Protective sheath |
Harvia WL550 (reduces clearances to 4.7" all sides) |
| Floor plate |
Harvia WL110 (22"x25"x2.5" / 560x635x60mm) |
| Pipe-model water heater |
Compatible - chimney-mounted (sold separately) |
| Flue pipe extensions |
Harvia WZ11520, WZ11550, WZ115100 |
What's included
Harvia PRO 36 wood-burning sauna stove
Cast-iron framed glass hatch (reversible door direction)
Frame
Grill
Adjustable feet
Installation and operating instructions
2-year limited warranty (consumer use)
Required (not included): 132 lbs AC3020 stones - 3 boxes, 10-15 cm (additional box recommended); 6" North American flue adapter (Harvia WZ115155). Optional accessories (sold separately): WL550 protective sheath (reduces clearances to 4.7"); WL110 floor plate; pipe-model chimney water heater; flue pipe extensions (WZ11520, WZ11550, WZ115100). A licensed chimney professional is recommended for all flue installations.
Why the Harvia PRO 36 stands out
31kW - a powerful pack for large saunas and groups
Harvia describes the PRO 36 as a powerful pack for big saunas that will never run out of steam - a direct statement about what 31kW with 132 lbs of stones delivers for a large group. For a log cabin sauna up to 1,271 cu ft, an outdoor sauna in a cold climate that needs maximum output, or a family sauna where multiple rounds of bathing for a large group are the norm, the PRO 36 provides the output that lighter heaters cannot sustain. The fire charges the stone mass rapidly and the heat holds long after the fire dies down - Harvia states plainly that the stones make it possible to enjoy the sauna for a long time even if the fire temporarily goes out.
132 lbs of stones - hearty steam for a larger group
At 132 lbs (60 kg), the PRO 36 stone load is the largest in the PRO Series - three times the per-box count of the PRO 20's two-box load. The larger stone mass means more thermal energy stored during the fire, more dense steam available per ladle of water, and more sustained heat after the fire dies down. For a sauna room in the 494-1,271 cu ft range with multiple bathers bathing in rounds over several hours, the 132-lb stone capacity is what makes the session self-sustaining. The fire sets the temperature, the stones hold it.
Stainless steel air-flow spoiler for efficient combustion
The PRO 36 includes a stainless steel air-flow spoiler that optimises the combustion air distribution through the fire chamber, improving burn efficiency and the rate of heat transfer to the stone mass. The fire chamber and fire channels are designed by Harvia to ensure the sauna heats quickly and the fire burns cleanly - less smoke output, more complete combustion, and better heat transfer to the stones. The result is a faster heat-up for a 31kW stove that is heating a large room, and a cleaner-burning fire that requires less chimney maintenance over time. The spoiler is a stainless steel component built into the PRO 36 body and requires no setup or adjustment.
WL550 protective sheath - 19.69" to 4.7"
The PRO 36's standard clearances of 19.69" on all sides from combustible materials are appropriate for 31kW but can constrain bench placement in a large sauna room. The optional WL550 protective sheath (sold separately, model-specific for the PRO 36) mounts around the stove body and reduces those clearances to 4.7" (120mm) on all sides when installed. For a large sauna room where bench layout needs to be optimised relative to the stove position, the WL550 is the solution that brings the PRO 36's safety clearances in line with smaller heaters - without compromising the output. The WL110 floor plate (sold separately) is also available for installations where floor protection beneath the stove is required.
Stainless steel front, top and ash box - easy long-term maintenance
The PRO 36 uses stainless steel on all three surfaces that are most frequently handled during a sauna session: the front face, the top, and the ash box. Stainless steel is resistant to heat discolouration and cleans easily with no special treatment - important for a stove that is in regular use. The graphite black painted steel sides complete the Pro Series finish. The cast-iron glass hatch on the front face is reversible and fills the sauna room with the warm glow of the fire throughout the session. Adjustable feet allow the stove to be levelled on any floor surface.
PRO Series platform - PRO 20 and PRO 36 compared
The WKPR36M is the large-sauna configuration of Harvia's PRO Series. The same Pro Series platform is available at 24.1kW for rooms from 283 to 706 cu ft (PRO 20, WKPR20M) and with integrated water tanks in right-side 30-litre (PRO 20 RS) and left-side 20-litre (PRO 20 LS) configurations, as well as exterior-feed wall-penetration variants (PRO 20 SL and PRO 20 Duo). The PRO 36 is specifically positioned for the 494-1,271 cu ft range where the PRO 20's 24.1kW is not sufficient. Both use the same graphite black and stainless steel Pro Series finish, the same 115mm flue standard, and both are compatible with WL550 protective sheath. Made in Finland by Harvia. We are an authorized Harvia dealer.
About Harvia
Made in Finland - CE Certified - PRO Series - Large Sauna
Harvia PRO 36. 31kW. 494-1,271 cu ft. 132 lbs of stones. A powerful pack for large saunas.
Harvia is a Finnish sauna and spa company established in 1950. The PRO 36 is the 31kW configuration of Harvia's PRO Series - the classic high-output heater for large sauna rooms, log cabin saunas, outdoor saunas in cold climates, and group bathing. Graphite black body with stainless steel front, top and ash box, cast-iron glass hatch, stainless steel air-flow spoiler, and adjustable feet. 132 lbs AC3020 stones (3 boxes) and a 6" North American flue adapter are required and sold separately. Pallet delivery. We are an authorized Harvia dealer.
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31kW wood-burning - 494-1,271 cu ft - no electricity required
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132 lbs AC3020 stones required (3 boxes) - hearty steam for large groups
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Stainless steel air-flow spoiler - graphite black body - stainless front and top
- Safety distances: 19.69" all sides (combustible) - 4.7" with WL550 sheath
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115mm flue - 6" adapter required - pallet delivery - CE and EAC certified
PRO 36 vs PRO 20 vs Legend 300 - large sauna stove selection guide
PRO 36 vs PRO 20 vs Legend 300 - which large-sauna wood stove is right for your room
Three configurations serve buyers in the large-sauna wood stove category. PRO 20 WKPR20M: 24.1kW, 283-706 cu ft, 88 lbs stones (2 boxes), 4" side and back clearances - the right choice for rooms up to 706 cu ft where tighter safety clearances and a lighter stone load are the appropriate specification. PRO 36 WKPR36M (this listing): 31kW, 494-1,271 cu ft, 132 lbs stones (3 boxes), 19.69" clearances all sides (4.7" with WL550) - for large rooms from 494 to 1,271 cu ft where maximum PRO Series output, a larger stone load, and a stainless steel air-flow spoiler are required. Legend 300 WKLE36M: 23.5kW, 494-989 cu ft, 573 lbs stones (13 boxes) - for buyers who prioritise maximum stone mass and the longest sustained heat after the fire over raw output. Choose the PRO 36 for the 494-1,271 cu ft range where 31kW of PRO Series output, efficient combustion, and a practical stone load of 132 lbs are the right balance for the installation.
Manuals and Documents
Warranty
2-year limited warranty (consumer use)
The Harvia PRO 36 is covered by Harvia's 2-year limited warranty from the date of purchase for consumer use. The warranty covers defects in manufacturing and materials under normal use conditions. The warranty does not cover damage caused by improper installation, use of incorrect stone type or size (non-AC3020, or stones outside the 10-15 cm specified diameter range), operating without the required stone load, failure to follow the installation and operating guidelines in the manual, damage from inadequate chimney maintenance, or soot fires. A licensed or certified chimney professional is recommended for all flue installation and regular chimney sweep maintenance. Proof of purchase from an authorized Harvia dealer is required for warranty claims. We are an authorized Harvia dealer.
