What size bathroom fan? You'll need to join it with ducting or weight of the scrubber will most likely pull the fan housing off the wall. That's if it would fit at all? Sizes are 4,5,6,7,8,9,10,12 and on. I use a 5 & 12 inch RVK set up. Have you considered removing the bathroom fan and getting a RVK or similar?
Golder Avater:What is a RVK setup?I'm wondering how well a bathroom fan will work as apposed to a fan like this "http://cheaphydroponics.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=CH&Category_Code=BLOWERS". The AAB60.
Stew. The size of fan depends on room size. You need to exchange the grow room air from 4 to 6 times a minute. It may seem excessive, but it;'s all about making the plants comfy and controlling the heat. Many many many people complain of heat when growing, and it's nearly always under-rated extraction that's the cause. You really want extraction that you have total control over. So you can turn it up and bring the temperature to the plants lower comfort zone, and turn the extraction down, to raise the rooms temperature. If you don't get the extraction right (as I had the first 2 grows) you'll start looking at AC units to get over it. If you get the correct extraction to start with, and outside ambient temperatures aren't higher than the plants 'upper' comfort zone, you'll be well heeled for a successful grow. If outside temperatures are higher than the plants upper comfort zone, then no matter how much air you pull across the room you won't lower temps below this. Then an air cooler of some description is inevitable. Of course, you can reduce the optimum extraction and cost by having less lumens and/or heat, but what if you find the room a success and want to grow more? Or SOG? So needing more lighting you'll find the cheaper extraction not being able to cope. At the end of the day, you/we all want a quality product balanced with good yield. If you want to be able to balance this, you'll need to have your extraction well worked out and more than your requirements. If you give details on Width, Depth, Height, How many lights and what type/wattage, and I can calculate what you need. The RVK fan is commonly known as a ruck fan in the UK but they're in the link. http://www.progrow.co.uk/acatalog/extractors-brackets.html?referrer=adwords&keywords=rvk_fan
