The 14 inch Maxfan is the best. 2.5 amps, super quiet and powerful. One bad thing - I haven't been able to find a controller that allows you to properly adjust fan speed. I've purchased the CAP fan speed controller as well as the other popular fan speed controllers...and no luck.
I have several and will never use another fan again. well, unless something else comes out that is better... but nothing out yet. the 14" is quieter than the 10". The 14 runs at a lower rpm allowing it to be quieter. also, you can get the correct speed controls for the bigger fans at frys for a reasonable price compared to the max fans model.
if you can handle the 12 being a little noisier i'd go with that one, it'll save you money on cost of fan and cost of ducting/reducers and takes up less space.I looking at getting the 10in or 14in max fan. I would like to cool two rooms off one fan. 4000k of light. I have 2 6in vortex fans now, but they are 3 years old and are now very very loud. Any input would be great.
You can't go wrong with a max fan. The fans you are looking at are two different animal's though. If your looking for efficency the 10" is one of the best in it's class. It uses 1.9 amps to push 1000 cfm The 12" users over 4 to push 1700 cfm, It will push that throuh the right can filter and 25 feet of ducting though. I should mention that by push I mean output cfm . You should always try and pull your air through rather then push but you get the idea! The 14" moves the same amount of air as the 12 and does so with only 2.3 amps or so. The cost is this number will drop off faster then the 12 inch with any kind of load. Think of the 14 as a diesel engine and the 12 as a diesel with a turbo. The 12 is a real work hourse but does so at the cost of twice the amprage draw as the 14 inch max. I am still unclear how you plane to use the fan. You say you want to cool 2 rooms with it. That could mean you want to pull through your lights to cool or it could mean you want to exhaust air to cool. Ideally you would utilize both ways. A constent flow through your hoods and a high mounted exhaust hooked to a climate controller. I have used 10 and 12 " max fans. I wish the 14's were avaliable when I got the 12 inch cause for my situation it would have been a bit more energy efficent. Also you can run the 8 and 10' on a regular fan reostate. The problem is when you do this the motors are cooled with the air flow. If you reduce the air flow to much then the motors burn out. The 12 " uses a different motor. It actually sounds about like a jet starting up. lol It is loud. Every thing comes at a cost. Figure out how you plan to use the fan and the most efficent use for your intended purpose and go from there. You can not go wrong with any of the max fan's line. I would not be so concerned about saving a few buck over duct sizing between 12 and 14 inch, It is neglagable when you consider you might be running the fan for a decade or 2. remember the 12 is for long duct runs to maintain air flow. The 14 is for quiet energy efficency. The 12 uses 2 times the power as the 14 inch. Depending on your circut load, that could be the difference between using 1 breaker or adding a second circut. Also check ebay for used items. I have seen the 12's go for as low as 200 bucks. Peaceif you can handle the 12 being a little noisier i'd go with that one, it'll save you money on cost of fan and cost of ducting/reducers and takes up less space.