Connecting a boiler to the chimney
Choosing a chimney is a challenge for many people looking to buy a new boiler for their home or business. This short article offers basic, practical advice on choosing the right boiler and chimney for your building.
Connecting the boiler to the chimney correctly
The connection must meet several requirements, and not every house has the same height or floor area. Consult a chimney professional or designer about the installation. The chimney must also reflect current heating requirements because it has a major effect on the efficiency of the whole heating system and on comfort at home. Special standards and laws set out the requirements for chimneys. Here are practical examples for houses, business premises and industrial buildings.
Bungalow
Single-storey houses are popular because of their low running costs, but they still need to meet the requirements for proper operation. For this type of house, the chimney should be at least 6 m high. A shorter chimney may not provide sufficient draught because it cannot remove the volume of flue gases produced by the boiler quickly enough. The chimney diameter matters too. We recommend at least 20 cm and a minimum draught of 23 Pa. If the chimney is higher, its diameter may be smaller, but by no more than 20 cm. For a bungalow with an area of about 80–100 m², a boiler with an output of 15–30 kW is suitable. To achieve maximum boiler output and a long service life, install a buffer tank and an Oventrop mixing unit with the boiler.
Two-storey house
For a two-storey house, the chimney should be at least 10 m high. A shorter chimney may not provide sufficient draught because it cannot remove the volume of flue gases produced by the boiler quickly enough. Compared with a bungalow, the diameter should be narrower, but at least 16 cm, with a minimum draught of 23 Pa. If the chimney is higher, its diameter may be smaller, but by no more than 16 cm. For a two-storey house with an area of about 200–250 m², a boiler with an output of 15–30 kW is suitable. To achieve maximum boiler output and a long service life, install a buffer tank and an Oventrop mixing unit with the boiler.
Small business premises
Small businesses, apartment buildings and schools often need to heat larger areas, such as offices and warehouses. The chimney’s height and diameter must allow the boiler’s flue gases to be discharged properly. A designer specifies them according to the type of building; chimneys can range from 7 to 15 m in height. A chimney that is too short may not provide sufficient draught because it cannot remove the volume of flue gases produced by the boiler quickly enough. The minimum chimney diameter is 30 cm and the draught is 23 Pa. We also design for small businesses, so we have developed boilers with a large loading chamber and combustion efficiency of up to 92%. For premises of about 1,000 m², a boiler with an output of 30 to 55 kW is suitable. To achieve maximum boiler output and a long service life, install a buffer tank and an Oventrop mixing unit with the boiler.
Boilers for houses and small business premises
Small business premises
Small businesses, apartment buildings and schools often need to heat larger areas, such as offices and warehouses. The chimney’s height and diameter must allow the boiler’s flue gases to be discharged properly. A designer specifies them according to the type of building; chimneys can range from 7 to 15 m in height. A chimney that is too short may not provide sufficient draught because it cannot remove the volume of flue gases produced by the boiler quickly enough. The minimum chimney diameter is 30 cm and the draught is 23 Pa. We also design for small businesses, so we have developed boilers with a large loading chamber and combustion efficiency of up to 92%. For premises of about 1,000 m², a boiler with an output of 30 to 55 kW is suitable. To achieve maximum boiler output and a long service life, install a buffer tank and an Oventrop mixing unit with the boiler.
Boilers for industrial buildings
A solution for insufficient flue-gas draught
If technical limitations prevent the chimney for your house, business premises or industrial building from reaching the required height, there is a solution. We have developed an additional flue-gas extractor to improve draught from the boiler to the chimney, even when the chimney parameters are insufficient.
