It is important to provide adequate chimneys already in the planning of your home. A chimney must be matched to the furnace rating as well as the planned heating system and heating material.

Types

Today’s standard is a three-layer chimney consisting of a fireclay pipe, thermal insulation and an outside casing. There are two widespread variants :

Variant A: Back-ventilated chimney

• Back-ventilation channels are provided between the insulation and the firestone.
• These prevent sooting of the chimney and accumulation of moisture in the firestone and in the insulation.

Variant B: Moisture-resistance of chimney

• Glazed fireclay, stainless steel chimney, and glass or plastic chimneys are largely immune to moisture.
• Protect the insulating layer, especially suited for HHV technology
• Condensate is collected and directed into the sewer.

Dimensioning

• The cross-section of the chimney needs to be properly dimensioned.
• The cross-section varies according to fuel: Solid fuel requires a larger cross-section, while a smaller cross-section suffices for natural gas and oil.
• HHV technology for oil and natural gas requires a chimney that is impervious to moisture (greater condensation) and a drain.
• Before installing a new heating system or upgrading, always have the chimney checked.