An outdoor air conditioner is designed to be an all-weather device, and nothing should impede its airflow since heat transfer from the indoor equipment to the outdoor HVAC equipment requires that this outdoor system radiates energy to the atmosphere; You could destruction your HVAC system when you cover or block the outdoor unit.
You may have thought of protecting your air conditioner during the off-season to prevent elements of weather from destroying your unit, but your outdoor equipment is designed to withstand, then any dirt or dust that may gather on your air conditioner is washed away with rain and snow; While you may know that rain and water will destroy the unit, its internal equipment is protected against water, and rainwater has a designated path to drain the water out to prevent your equipment from accumulating moisture! However, you may need to cover your equipment after summer time to prepare for fall because your outdoor equipment is not built to keep out debris, leaves, seeds, or nuts! During fall, leaves and seeds get into your outdoor A/C unit, and this may cause moisture to build up to where seeds and debris have accumulated, and the moisture build-up will end up causing corrosion to your equipment and blockages to your drainage system, if you choose to make your cover, it is advisable only to cover the top of your outdoor A/C unit… Covering the entire equipment will lead to moisture getting trapped inside, which will cause your equipment to rust and corrode.
When you fully cover up your unit, you will have provided rodents a place to stay instead of repelling them away.