Diy Indoor Air Conditioner Covers For Wall Units . 33% off s/m/l window air conditioner cover waterproof windproof snowproof dustproof air. It looks more like a piece of art than a cover for an ac or heat register! Ductless A/C+ Heater cover to make it look nice in my little craftsman from www.pinterest.com Best 5,000 btu air conditioner:. Use fabric adhesive to adhere the fabric to the plastic sheet. View in gallery essential maintenance air conditioning unit.