How do I know if I have an existing warranty on my furnace, air conditioner or HVAC system? Find the label on the outside of the element of your home comfort system for a manufacture date. Equipment less than five years old may have a warranty, but also may not subject to the manufacturer. Warranty terms and conditions change by manufacturer and the installing company. Knochelmann Service Experts Heating & Air Conditioning can verify the warranty status of your heating and cooling system via System Inspection. We also offer a Platinum PLUSTM Protection Plan for residential heating and air conditioning systems, regardless of the equipment age or manufacturer warranty status. Back To Frequently Asked Questions