Heater database · Kastor
Kastor Karhu 20
Kastor Karhu 20 is a wood-burning stove rated for sauna rooms of 282–702 ft³ (8–20 m³). Classic Finnish steel stove, the US version (Karhu Home) sold by Finnleo.
WoodWood-burning stove
282–702 ft³rated room · 8–20 m³
71 lbstones · 32 kg
–nominal output
Rooms it fits
Indoor rooms with insulated walls, a 7 ft ceiling and a glass door, which counts extra. Wood stoves are rated by room volume, not by kW. For your own room, glass, masonry or log walls, use the calculator.
| Room | Counts as | Fit |
|---|---|---|
| 4 × 5 ft | 199 ft³ | Too big for this room |
| 5 × 5 ft | 234 ft³ | Too big for this room |
| 5 × 6 ft | 269 ft³ | Too big for this room |
| 6 × 6 ft | 311 ft³ | ✓ Rated for this room |
| 6 × 7 ft | 353 ft³ | ✓ Rated for this room |
| 7 × 8 ft | 451 ft³ | ✓ Rated for this room |
| 8 × 8 ft | 507 ft³ | ✓ Rated for this room |
| 8 × 10 ft | 619 ft³ | ✓ Rated for this room |
Similar stoves from other brands
- Narvi Aito AK-57318–706 ft³
- Narvi Aito AK-57K388–812 ft³
- Narvi Aito AK-47283–424 ft³
- Narvi Aito 68494–918 ft³
Source
Rated room range and stone load from Kastor's product information, checked October 2026. Ranges are the manufacturer's calculated room volumes; check the manual for safety distances, and have a licensed electrician make the connection.