You’ll want to look for a manufacture date. This is usually located on a label on the surface of your system.
If your equipment is newer than five years old, it might still be under warranty. Having said that, warranty terms and conditions vary between manufacturer and installing company.
At Boehmers/Cronin Emery Service Experts, we can confirm your warranty status with a system inspection. We also provide HVAC service memberships in Kitchener for residential heating and AC units, regardless of equipment age or manufacturer warranty status.