Hello! My chimney in the basement had once a ventilator, but it fell out after 15 years of use (yeah…) and the ugly hole is there, so I decided to make a new one. It's nothing fancy and it works. Cost me nothing, like usual, might not be as strong as those industrial fans but hey - it's homemade :D
You can see the whole DIY right here: http://9v.lt/blog/diy-ventilator/
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