You’ll want to look for the date it was made. This is typically found on a label on the exterior of your system.
If your unit is newer than five years old, it may still be warrantied. Having said that, warranty terms and conditions vary between manufacturer and installing company.
At Service Experts Heating & Air Conditioning, we can confirm your warranty state through a system inspection in Canada for residential heating and air conditioning units, regardless of system age or manufacturer warranty status.