Product review (1 stars): Very Disappointing Customer Service
I found this product on Amazon but ended up having to buy it direct through Global appliances/Rangehoodstore.com because I wanted the chimney cut to a custom length of 20" due to a short ceiling.  When placing the order, I requested that they send everything that was needed for a ductless installation since this is part of a remodel and there's no way to duct this hood without significant cost. They told me I had everything I'd need. I researched ductless installations and watched installation videos so I'd be prepared.  When I got the hood, I realized they didn't send me an air deflector to direct the hot, humid air out of the grilles in the top of the chimney.  I checked their installation manual and, sure enough, the manual stated that I should use the air deflector to direct the air out of the grilles in the chimney. So, I emailed them to say I was missing parts. They claimed I didn't need that part.  Every installation video and manual (including theirs) that I looked at for ductless hoods use an air deflector to make sure the hot, humid air goes out the grilles and not up into the ceiling.  I quickly realized why they didn't tell me to purchase the deflector - when they cut the chimney down to 20", they did so in a way that put the grilles below the blower so there would be no way to use the air deflector to push the air out of the grilles.  I contacted them and explained that I was very concerned that hot, humid air would be going right up into our floor joists (your ceiling will have a hole in it when you install a hood - the hole is for the wiring to come down and for a support system to be installed to hold the weight of the hood).  I've read on numerous sites that no one should ever vent the air from a kitchen hood up into the floor joists or attic.  If the air is greasy (if we forget to change the carbon filter soon enough) it could be a fire hazard.  Humid air in the floor joists could lead to mold, etc.  I asked to exchange the chimney for one with the grilles at the top like in the drawing they show here on Amazon so I could use the air deflector shown in the installation manual. By the way, the installation manual stated that if the directions for air exhaust were not followed, the company would not be responsible for any damage so I really wanted to follow the installation instructions so as not to void my warranty.  They, initially, agreed then emailed me at the last minute to say I'd be fine as is.  I haven't heard from them since.  So, basically, they left us with a hood that does NOT look like the drawing you see here on Amazon that has the grilles on the top so the air deflector can push the air out.  So, beware if you need this hood custom cut. I asked them if NT Air knew they were telling buyers to ignore the installation instructions and let air go up into their ceilings.  They assured me (insert laughter here) the hot air would not go up into our ceiling but sink down to the grills and I'd have no warranty worries.  The moral of the story is, once they have your money, they'd don't seem to care how well the product will work for you.  So, if you need the chimney height modified, buy elsewhere.