Reducer Ø 315 - 250 MM

This reducer brings a 315 mm duct down to 250 mm. It is a single fixed size in galvanised steel, and both ends slide directly into spiral pipe or flexible ducting.

Where 315 mm comes from

The sizes you meet in a grow room stop at 250 mm, because that is where nearly every inline fan and carbon filter ends. 315 mm is the next standard size above it and comes from general ventilation work: roof outlets, existing extraction ducts in a commercial building, duct fans of another order.

So this piece is almost always an adapter onto something that was already there. You did not buy a 315 mm system, you inherited one, and this is the part that joins your installation to it.

Bear in mind that the narrow end limits your whole system. Whatever hangs above the 315 side, no more passes the 250 side than a 250 mm duct can carry.

Technical Specifications:

• Inlet: Ø 315 mm
• Outlet: Ø 250 mm
• Material: galvanised steel
• Mounting: both ends slide into spiral pipe or ducting

Frequently asked questions

Does it fit over the pipe or inside it?
Inside. Both sides go into the duct, after which you seal with tape or a clamp.

Can I fit it the other way round?
Yes, 250 to 315 works just as well and is the kinder direction for airflow.

Are there other sizes in this format?
Of this 315 mm transition we stock only this one. Below 250 mm you will find eight combinations on the standard reducer.