24 HOUR WARNING
"The compressor of an air conditioner is a bit like a small electric motor in that it has gears and turning parts that require lubrication. The lubrication in the air conditioner compressor comes in the form of oil, typically located in the compressor case itself. When an air conditioner is turned on its side, this oil settles on the bottom half of the compressor and potentially deprives part of the compressor of oil, which can lead to damage and, eventually, compressor burnout.
If an air conditioner has been stored on its side, or if it has been shipped that way, take care to ensure it has been turned horizontally for a period of at least 24 hours prior to running the unit. This allows sufficient time for any oils and lubricants to resettle back to their proper levels, providing protection for internal gears and moving parts.
When you move the unit to the location where you plan to install it, you may have to set it on its side temporarily prior to setting it in place. It's fine to do this, as long as you don't install the unit sideways and you don't turn it on for 24 hours."
