Good temperature control ensures that fermentation remains within the range of conditions best suited for your yeast of choice. This might be as high as 70–80°F (21–27°C) for Belgian ales or as low as 45–55°F (7–13°C) for German lagers.
Here are a few ideas, roughly in order from least to most effective (and, correspondingly, least to most expensive) for keeping your cool.
- Evaporative cooler
- Temperature-controlled chest freezer or refrigerator
- Jacketed conical fermentor
Thinking about opening a brewery? Start with this video class to learn the basics.