Effectiveness is influenced by capacity of unit. If you are trying to mount a 270 cfm fan more than 30" above cooktop, then it may make noise but will do little to clear the air. If it is 1000 cfm, then it can be higher than 30". So the answer is "it depends". Most people don't mount them more than 36" above the cooktop unless it is a really high powered unit.

I had purchased hafele hob 10 months back... I got it serviced 6 times... Now i requested for replacement with new one... Still they have not attended my request...

Sophie, Patricia you are right cleaning the crystals would be a hell of a job. Hence I would like to look at designs like the other pic I attached which is I believe from the e.ion range of Falmec. As I have mentioned before this is a second chimney. The primary chimney hood is above my gas job in the kitchen countertop and is the main and daily area for cooking. This is the secondary area which I plan to use for some quick heating, occasional stir fry etc. The pendant chimneys that I have come across in brands like Elica and Falmec do not require ducting. The filter needs to be changed every 6 months or more. With my kind of usage I am assuming I would need to change it even later. What I am looking for is different brands which have pendant chimneys. Right now I am only aware of Elica and Falmec. I know Siemens and Bosch don't have it. Siemens has 2 models which are like a flat rectangular panel to be attached to the ceiling or false ceiling. But the cost is same as the Falmec chimney. My only respite may be the cylindrical Isola chimney models from Faber or even Hafele which are ip within budget.

HI there, Yes, our site can't upload renderings unless they are jpgs or png, so i have converted them for you..