- Harwell, Oxon
I built a downdraft system a couple of years ago which used a Torin centrifugal fan direct coupled to a 3000 rpm single phase motor. This worked fine until last week when the impeller became detached from the hub. Not a huge surprise considering the original fan was designed to run at 1500 rpm. This got me looking for a replacement. A new Torin fan was offered at £700+ - not a remote chance of me going for this. So I searched the bay using some creative phrases and came up with hydroponics box fans. I bought a 4250 m3/hr single phase fan in an acoustic box for £35. This has 250mm suction and discharge ports so with a 250-150 reducer will fit my current discharge hose. The existing 150 and 100 hoses fitted to my table were installed on the new box (now complete with castors) very easily. Job done, and all for a fraction of a) a new fan from Torin and b) even a new box fan (they retail at anything up to £390.