The answer to 'air conditioner making noise' is that there are several common causes, including worn or loose parts, refrigerant leaks, and issues with the compressor or fan. Symptoms can include rattling, grinding, or screeching noises. Solutions may involve tightening or replacing components, repairing leaks, or calling a professional HVAC technician.
If the noise is persistent or you're unsure of the cause, it's best to have a professional inspect the system. Attempting DIY repairs on an air conditioner can be dangerous and may even void the warranty. A qualified HVAC technician can diagnose the issue and provide the appropriate repair or replacement services.