If you have a chest freezer that you won't be plugging in, it is best to leave the lid closed. Keeping the lid closed will help protect the interior of the freezer from dust, debris, and pests. It will also prevent any potential accidents, such as someone accidentally falling inside the freezer.
Closing the lid creates a seal, which helps maintain a more stable environment inside the freezer. Leaving the lid open would allow air to circulate freely, which could lead to the accumulation of dust and dirt inside. Additionally, an open lid might also encourage pests to enter and make the freezer their home.
To ensure the freezer remains in good condition and ready for future use, clean it thoroughly before closing the lid. Remove any food residues, clean the interior, and dry it out to prevent any moisture-related issues.
If you plan to keep the chest freezer unplugged for an extended period, you may want to periodically check on it to ensure there are no signs of mold, mildew, or unusual odors when you eventually decide to use it again.