Roasting coffee in winter is pretty challenging, when the temperature drops below 0c (32F) it is extremely hard to reach 500F for 2nd crack (at least for my Fresh Roast SR700). You would NOT want to do it in your kitchen, trust me. So this is an alternative way to contain the roaster and divert the smoke outside of the house. I got the coleman cooler from Walmart, drilled some holes and mounted the 4″ ducts (one at the top and one on the side). Then attached those flexible hoses to two duct fans. It’s pretty easy weekend DIY project.
In some cases, I have to manually adjust the speed to lower the fan speed of to get the roasting temperature to go beyond 500F (Yes, low speed = high temperature in fan-based coffee roasting. Google it). The problem is that the ambient temperature in the garage still so cold, even I put a small electric heater to warm the air intake.