2001 Kia Optima Q&A
2001 Kia Optima Question: is the a/c compresser a must have working for the car to run properly?
The only issue I see is that if the compressor was to seize up the drive belt could break and cause damage. This is very rare but possible. You of course won't have any a/c cooling, but you will also lose the ability for the defrost to work as well as it should. (The A/C helps to remove moisture from the air that is directed to the windshield when the defrost is used) - Bret Bodas
The fan belt/drive belt that drives the air conditioning compressor also drives the power steering pump so if the air conditioning compressor failed causing the belt to brake you would also loose the power steering assist and the belt may jam and cause the second belt that drives the alternator and water pump to fail as well. - patrick mannion