MULTIKERAM LAS Chimney System - Leier

Short description

The top of the Leier range. W3G hybrid system with a pre-insulated flue liner, the only one that takes condensing boilers. Four diameters, 140 to 200 mm.

Full description

LAS stands for the combined air and flue gas system: the chimney carries the flue gas up and the combustion air down, so a sealed-combustion or condensing boiler draws its air from outside instead of from the room. In an airtight, well-insulated house that is not a refinement — it is the difference between a boiler that works and one that starves.

The build differs from MULTIKERAM: the fireclay liner arrives already insulated, positioned by a centring ring inside the outer block. Fewer components per metre, less to get wrong on site.

Like MULTIKERAM it is W3G rated, so it handles both a soot fire and the condensate of a low-temperature system. Leier positions it for houses where the fuel is still undecided, and recommends it for nZEB — nearly zero-energy — buildings.

Key benefits

• Combined air and flue gas system — combustion air from outside the room
• The only Leier system for condensing boilers
• W3G certified: soot-fire resistant and moisture insensitive
• Pre-insulated fireclay liner with a centring ring — fewer parts per metre
• Recommended for nZEB and airtight houses
• Four diameters: 140, 160, 180 and 200 mm

Technical specifications

• Product type: combined air and flue gas ceramic chimney system
• Brand: Leier
• Range: MULTIKERAM LAS
• Certification: W3G
• Flue diameters: 140, 160, 180 and 200 mm
• Outer dimensions: 35 x 35 cm (140), 40 x 40 cm (160 / 180), 48 x 48 cm (200)
• Weight: 103–132 kg per linear metre, depending on diameter
• Consumption per linear metre: 1 insulated liner, 1 centring ring, 3 outer blocks
• Use: gas and oil including condensing, pellets, wood, mixed burners, fireplaces, stoves
• Sold by: linear metre
• Delivery: made to order, subject to supplier stock

Recommendation

Take this one if the house is airtight, if the boiler is condensing or sealed-combustion, or if the fuel is not settled. In an older, leaky house on a wood boiler it is more chimney than the job needs — LSK does that work for less. Size the flue from Leier's diagram using the appliance output and the useful height, and order the full height in one go, terminal set included.