I was wondering if there is a cheap alternative to a temperature / humidity controller, one thought I had was hooking up an old wall thermostat to set off extra fan at a certain temperature or something like that but I'm not sure how that would work. What are some ways you guys control the climate without a controller
You can get CAP controller for $100 or so ... I think you not going to save much by making one unless you have all the tools , knowledge and parts...And to be honest with you , you can do just fine as long as your grow room temp stays on or below 82f and not lower than 65f and humidity level on 30-40%...
I do not know what could be a good options but I just saw this DIY: Build Your Own Environmental Controller on twitter - seems to be a climate controller with open source,so you do not have to buy an expensive controller.