Cooker hood ventilation - rigid piping

rentalforever

I'm using rigid spiral piping for our vented cooker hood which has a 150mm vent so I can maximise air flow and minimise noise.

I ordered a 90-degree bend spiral pipe thinking it would attach to the hood vent hole but it doesn't fit - it's basically the same size. Am I missing a component, if so what do I need and does this site sell it: https://www.ventilationland.co.uk/spiral-ducts-and-fittings - I ask as I bought the rest of the kit from this site.

grumbler

I have no any experience in this, but from the photo  the bend diameter seems to be a little smaller then the vent hole one. If so and looking at the rubber ring and the round stop, is it not supposed to be pushed into the hole?

tacpot12

You aren't missing a component. That style of ducting isn't designed for domestic cookerhoods, it's an industrial product designed for industrial ventilation. 

You need something like this: Blauberg Plastic Circular 90° Bend - 6"/150mm - White | ElectricalDirect
plus a small section of 150mm plastic duct (like this Blauberg 6"/150mm PVC Solid Ducting - 1500mm - White | ElectricalDirect but cut to length). Use Duct Tape to seal the sections together. 

Domestic cookerhoods are designed to have a straight peice of duct directly attached to them, although you can occasionally get appliance connectors like this one: Manrose Round to Rectangular Flat Channel Appliance Connector Elbow 90° Bend White 204mm | Ducting | Screwfix.com

I couldn't see any appliance connector for 150mm duct.  

rentalforever

tacpot12 said:

You aren't missing a component. That style of ducting isn't designed for domestic cookerhoods, it's an industrial product designed for industrial ventilation. 

You need something like this: Blauberg Plastic Circular 90° Bend - 6"/150mm - White | ElectricalDirect
plus a small section of 150mm plastic duct (like this Blauberg 6"/150mm PVC Solid Ducting - 1500mm - White | ElectricalDirect but cut to length). Use Duct Tape to seal the sections together. 

Domestic cookerhoods are designed to have a straight peice of duct directly attached to them, although you can occasionally get appliance connectors like this one: Manrose Round to Rectangular Flat Channel Appliance Connector Elbow 90° Bend White 204mm | Ducting | Screwfix.com

I couldn't see any appliance connector for 150mm duct.  

Well that makes me sad