If your system is making strange noises or also not keeping you as comfortable as it should it may be time to call the professionals. Whether you need a new. system or a simple repair a certified HVAC technician will inspect your system and also help you understand what is best. Most air conditioning systems last about 10 years. Once you hit the 10-year mark it may be time to start considering a new more efficient system to help you save money on utility bills.