You’ll want to look for a manufacture date. This is typically located on a label on the outside of your equipment.
If your system is newer than five years old, it might still be warrantied. However, warranty terms and conditions differ manufacturer and installing company.
At Service Experts Commercial HVAC, we can confirm your warranty standing with a system inspection. We also have HVAC service memberships in Toronto for residential heating and AC units, regardless of system age or manufacturer warranty status.