CombiSteel Converter Ø250mm-350mm 7216.0645

£70.58

+vat

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SKU: 7216.0645

Product summary

Size W/D/H (mm) x x

Product description

A stainless-steel duct converter designed to expand extraction airflow from 250 mm to 350 mm, ideal for stepping up to a larger main exhaust riser. A CombiSteel ducting converter for changing between 250 mm and 350 mm extraction duct sizes, with a 2 kg gross weight for practical fit-out handling.

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SPECIFICATION 5 facts · tap for all Gross / net weight2 kgBrandCombiSteelGTIN / EAN6017441147144TypeDuctingDiameter250 mm

Identity3

Brand CombiSteelcatalogue
GTIN / EAN 6017441147144catalogue
Type Ductingcatalogue

Size & weight2

Diameter 250 mmcatalogue
Gross / net weight 2 kgsite
THE WORKING VIEW

Why this ducting earns its place

Extraction systems need to scale smoothly as individual hoods merge into a central exhaust stack. When you're connecting smaller branch ducts to a larger main riser, a proper expander prevents bottlenecks and turbulence. This Combisteel converter handles the 250–350 mm step-up, ensuring the airflow accelerates into the larger duct without creating dead zones or pressure reversals that would choke the whole system.

At 2 kg, it's a substantial but still manageable component, built in stainless steel to withstand years of heat, steam, and grease in a commercial kitchen. The geometry is designed to guide expanding airflow smoothly, so you don't lose the suction that drives your individual hoods. In a busy kitchen, that's the difference between a hood that clears smoke instantly and one that lags when all burners are running.

Sizing ductwork correctly is often the hidden detail that separates a kitchen that breathes from one that feels stuffy and slow. This converter is part of that calculation—it's the component that lets multiple smaller extraction runs pool into a larger main without creating a bottleneck.

BEFORE YOU BUY

Questions, answered straight

A rough join creates turbulence, eddies, and uneven flow distribution. Some areas of the duct will slow down while others speed up, which disrupts the balance of your whole extraction system. A proper expander like this one ensures all the incoming flow merges smoothly into the larger duct.

Energy efficiency and cost. Smaller branch ducts use less material and take up less space where it matters (at the hoods). Stepping up only when you need to, via a proper converter, keeps the system lean and responsive. You're moving the right volume of air, not forcing too much through too large a duct.

Expansion actually increases the cross-sectional area, so velocity decreases—but that's normal and expected. The important thing is that the expansion happens smoothly via a proper converter, not violently through a mismatched join. The total volume of air moving is unchanged.

It's bolted or duct-clipped in place as part of your main exhaust stack, and all joints should be sealed with silicone to ensure an airtight fit. Your extraction designer will have sized the ductwork and specified the right converter for your kitchen's layout and airflow demand.

A correctly balanced extraction system has even suction at all hoods and doesn't draw air through unwanted gaps. Your installer should commission and test the system when it's first fitted. If hoods feel sluggish or uneven later, a professional duct cleaning or adjustment may be needed—phone 01792 732702 for advice.

That depends on your total hood flow and kitchen layout. This converter steps up to 350 mm, but you may need an even larger main riser depending on how many hoods are connected. Work with your extraction designer or installer to size the whole system as a unit.
See it in our Swansea showroom

Compare kit side by side and discuss delivery with the Craven team.

CombiSteel Converter Ø250mm-350mm 7216.0645 Product Data

Brand CombiSteel
Diameter 250 – 350 mm
Weight 2 kg
If you have any questions about the CombiSteel Converter Ø250mm-350mm 7216.0645 then please get in touch.

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