You’ll want to check for a manufacture date. This is usually found on a label on the outside of your unit.
If your equipment is under five years old, it might still be under warranty. At the same time, warranty terms and conditions differ manufacturer and installing company.
At Knochelmann Service Experts, we can check your warranty status via a system inspection. We also provide HVAC service memberships in Sharonville for residential heating and AC equipment, regardless of unit age or manufacturer warranty validity.