See the table below to select the right boiler and battery tank
The data is true with accumulator heating system in the case where the heating mode of the building is controlled by the heating system. The sizes considered are suitable for all houses. The heating frequency depends on the thermal insulation of the house. The choice is made on a heated surface area, with a height estimate of 2.5 to 2.7 m. The use of 50 cm firewood is common. Cast iron boilers suitable for 50 cm firewood have to be at least six ribs. A larger boiler can also be installed. The larger boiler will reduce the heating time and the number of heating cycles!
| Heated area m2 | up to 100 | 100-120 | 120-150 | 150-180 | 180-200 | 200-220 | 220-260 |
| Accumulation tank (L) | |||||||
| 100% radiator heating | 1000 | 1200 | 1500 | 1800 | 2000 | 2200 | 2500 |
| 50% rad + 50% floor heating | 700 | 800 | 1000 | 1200 | 1400 | 1600 | 1800 |
| 100% Floor heating | 550 | 720 | 900 | 1080 | 1200 | 1300 | 1400 |
| UNI | 4 | 5 | 6 | 7 | 8 | ||
| Boiler power (kW) | 20 | 28 | 35 | 44 | 53 | ||
| Firewood lenght max. (mm) | 330 | 440 | 550 | 660 | 770 | ||
| Capacity of the combustion chamber (dm3) | 51,6 | 70,3 | 89,1 | 107,8 | 126,5 | ||
| VIADRUS U-26 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Boiler power (kW) | 20-24 | 27-32 | 35-40 | 43-48 | 50-56 | 58-64 | 66-72 |
| Firewood lenght max. (mm) | 295 | 405 | 515 | 625 | 735 | 845 | 955 |
| Capacity of the combustion chamber (dm3) | 37 | 51 | 64,5 | 78 | 91 | 105 | 118,5 |
