You’ll want to find a manufacture date. This is frequently found on a label on the surface of your unit.
If your system is under five years old, it could still be under warranty. At the same time, warranty terms and conditions differ manufacturer and installing company.
At A-PLUS Service Experts, we can verify your warranty standing through a system inspection. We also have HVAC service memberships in Waldorf for residential heating and AC units, regardless of equipment age or manufacturer warranty standing.