Above our cooker/range/hobs there is a range hood.

How can I tell whether it is extraction (I.E. it takes the air outside)


re-circulation (I.E. It cleans it but sends it back into the kitchen)?

The wall you can see behind the hood is an interior wall, if relevant.

Left side

Right side


  • 2
    If there is a vent in front and air is coming out, it's recirc. In that case there are usually charcoal filters that need to be cleaned fairly often. Another clue is if there is a cabinet above the hood, and there is ductwork in it, it's probably vented. Apr 12, 2021 at 18:47
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    Am I missing something? Can you not just look on the wall outside to see if there is a vent?
    – SiHa
    Apr 12, 2021 at 19:12
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    @GeorgeAnderson I see a lot of these style of hoods, and only very rarely have they been vented (and that was in a brand new build house we bought) - in almost every case, they are supposed to be vented but just pull air up and through the filters. Its impossible to know whether its been properly installed with duct work and an actual vent without actually removing the housing and taking a look...
    – Moo
    Apr 13, 2021 at 3:04
  • 1
    I made my original comments before the OP posted additional pictures. To me, this looks like it's most likely vented to the outside. But as Moo said, impossible to know without getting into the attic (if accessible and not 2 story unit) and following the ductwork. BTW, I always get a kick out of the the terminology from our good friends across the pond, no one in the USA would use the term "extractor" for a range hood or bathroom vent fan. .....just sounds painful! LOL Take my British friends!. Apr 13, 2021 at 4:09
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    @Tom with regard to Moo's comments about possible improper installation of what should be a vented hood, I suggest you take one or both filters out and shine a light up there to see if there's any ductwork exciting through the wall or ceiling. Hopefully you can see through or past the fan.
    – brhans
    Apr 13, 2021 at 4:13

1 Answer 1


If it's a recirculator there will be vents on the front of the unit, and when it is running you will feel air coming out of those.

If it's an extractor there will be a pipe between 3 and 6 inches in diameter (wide) coming out of it. Typically you will see this in the cabinet above the extractor, if you have a cabinet there but sometimes it can go to the side or can be hidden behind a decorative cover. The pipe will go through an outside wall where you will see a small grate or hood. If it's not too high you will feel and maybe hear air coming out of that when the extractor is on. There may be similar grates or hoods on the outside wall for your clothes dryer, bathroom fans, and water heater you need to be sure which one you're looking at. Note, if the extractor is against an outside wall there may be no pipe inside, so the only clues would be the outside vent and the absence of a vent on the front of the unit blowing air when it's on.

  • Thanks. There definitely aren't any vents to the front of the unit (see photos I've added above). I think there might be what you describe as a cabinet - the sort of box at the top of the photos? So this suggests that it's an extractor?
    – Tom
    Apr 12, 2021 at 20:01
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    @Tom Yes, definitely an extractor. That box is just a nice cover hiding the exhaust duct inside. In my experience, recirculating models in this style tend to have the vents on the sides of the "chimney",where you clearly have none.
    – TooTea
    Apr 12, 2021 at 21:07
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    @Tom yes it's an extractor. The top part is what I meant by "decorative cover". Inside that is a pipe that goes, probably through the ceiling, to the outside.
    – jay613
    Apr 12, 2021 at 22:16
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    Note that its trivial to just not do the vent work and for these to be improperly installed - as per my comment on the question, Ive seen these installed in several properties and in all but one case they are supposed to be of the vented type but have no actual venting, they just suck the air up into the hood and ... well I guess it leaks back out.
    – Moo
    Apr 13, 2021 at 3:06
  • Regarding confirmation of the pipework, if you remove the filters on the bottom, you can see the often not particularly covered fan. You can use a flashlight to confirm the pipe going up, and if it's not far to the roof you can order a 6' USB camera for your phone or laptop very cheaply on aliexpress or amazon, attach it to a copper wire, metal coat hanger or fish tape for rigidity and shove it up the pipe to see where it goes without taking anything apart.
    – K H
    Apr 13, 2021 at 9:47

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