You’ll want to find the date it was made. This is typically found on a label on the surface of your unit.
If your system is newer than five years old, it may still be under warranty. Having said that, warranty terms and conditions vary between manufacturer and installing company.
At All American Air Service Experts, we can check your warranty state via a system inspection. We also have HVAC service memberships in Daytona Beach for residential heating and cooling units, regardless of system age or manufacturer warranty standing.