Kastor Karhu 22, 30 & 40 Wood Sauna Stoves

Kastor Karhu 22, 30 & 40 Wood Sauna Stoves

What makes Kastor Karhu sauna stoves stand out from competitors is their efficiency (up to 74.6%), which means maximal heating power with as little wood as possible.

Kastor is equally known for combining sturdiness and stone capacity in the most well-balanced way: the stoves are fairly heavy (142–284 lbs), which makes them durable and helps with storing heat, and there is room for plenty of stones (66–121 lbs) to bring ample löyly.

This combination translates to faster heat-up times than you’d get if the required stone masses were even larger.

The design with rounded corners is more polished and thought-out than the more typical, boxy designs.

Karhu is Finnish and means bear, so if you want a reliable grizzly in your sauna, this is the one for you.

Capacities & Dimensions

Kastor Karhu 22

• For sauna rooms from 424 to 777 cubic feet
• Nominal heating capacity: 14 kW
• Stone capacity: 55–66 lbs
• Efficiency: 70.2%
• Dimensions: 17.5 W × 19 D × 31 H in (450 x 485 x 785 mm)
• Heater weight without stones: 142 lbs

Kastor Karhu 30

• For sauna rooms from 706 to 1,059 cubic feet
• Nominal heating capacity: 17 kW
• Stone capacity: 77–88 lbs
• Efficiency: 72.3%
• Dimensions: 19 W × 19 D × 36 H in (490 x 485 x 915 mm)
• Heater weight without stones: 196 lbs

Kastor Karhu 40

• For sauna rooms from 1,059 to 1,413 cubic feet
• Nominal heating capacity: 15 kW
• Stone capacity: 110–121 lbs
• Efficiency: 74.6%
• Dimensions: 23 W × 23 D × 36.5 H in (580 x 585 x 925 mm)
• Heater weight without stones: 284 lbs

🔶 Not sure about sizing? Use our sauna heater size calculator.

Clearances to Combustibles

Kastor Karhu 22

• Ceiling clearance: 49 in (1 240 mm)
• Front clearance: 19.5 in (500 mm)
• Rear clearance: 12 in (300 mm)
• Side clearance: 12 in (300 mm)

Kastor Karhu 30

• Ceiling clearance: 51.5 in (1 310 mm)
• Front clearance: 19.5 in (500 mm)
• Rear clearance: 12 in (300 mm)
• Side clearance: 12 in (300 mm)

Kastor Karhu 40

• Ceiling clearance: 51 in (1 300 mm)
• Front clearance: 19.5 in (500 mm)
• Rear clearance: 12 in (300 mm)
• Side clearance: 12 in (300 mm)

🔶 If you want to reduce these minimum safety distances, metal sheets and cement boards are viable options.

• Check out a real-world example: How to Reduce Clearances
• 📄 Installation manual: Kastor Karhu 22, 30 & 40

Features

• 2-year warranty (in home use)
• Made in Finland, CE-certified
• Color: dark gray/silver
• Material: steel
• Elegant, rounded design & chrome front panel
• Floor model with adjustable feet in the front
• Reversible glass door (left- or right-hinged)
• Stone size: Ø 4–6 in (10–15 cm), required for operation & sold separately
• Flue connection location: top/rear
• Flue connection diameter: 4.5 in (115 mm) (see our chimney kits)

🔶 Need sauna stones? As they’re hard to find in the US & expensive to ship, we’ve partnered with North Shore Sauna that sells proper sauna stones mined in Minnesota & offers free shipping for orders over $100. When you buy through us, we get a commission and you get a discount code: if you buy six or more boxes, you get $50 off with the code SAUNAIS50.

Complete your setup: Buy real sauna stones

Shipping & Returns

🔸 Free shipping & no surprise charges: we handle all duties, taxes & customs fees.

🔸 Your order arrives damaged? No worries, our shipping policy has you covered.

🔸 Changed your mind? Returns are possible for unused items; return shipping costs apply.

🔸 Support: We’re here to help if you have any questions before or after purchase.

See full details: Shipping & Returns • Contact • Why Buy from Us