Check your owner's Manual for the model's specific warranty time period. If your proof of purchase is less than the warranty length, your product is still under warranty. If you no longer have your owner's manual, you can find it online under Instruction Manuals.
The limited warranty covers defects in materials and workmanship for all parts of the product, excluding filters & accessories. Damage from misuse, improper installation, alteration of the product or accidental breakage are not covered. Check your specific warranty for complete coverage information. If you are still unsure if your product is covered for further verification before returning your product.