Is this AC suitable for being left installed all year round or should it be removed in the winter time?

Hello - If you decide to keep your unit installed all year long, the indoor side of your unit may become cold to the touch when the weather gets cold outside. If you detect cool air coming from your unit, or frost, commercially available outdoor covers are sold and will help mitigate these issues. We hope this information is helpful. Thanks for taking the time to check with us. Best regards. -Don@GEA