You do not need to put a lid on your pot to cook with Joule. However, covering your cook setup allows Joule to heat the water more quickly. If you are doing a long cook or cooking at a high temperature, water will evaporate over time, so for best results, we do advise covering the pot around Joule with foil or plastic wrap. You can also purchase Flip Top, a lid made specially to fit Joule.
Do not fully cover Joule during cooking. Please leave the top of Joule exposed from the bottom of the cord up. Fully covering Joule may cause it to overheat and stop your cook. You may also lose your Bluetooth or WiFi connection if you cover Joule completely with a lid.