Nu-Calgon offers a three year limited warranty on all iWave products that covers any defects in material during normal use. If a warranty claim is made within the three year period, proof of purchase and proof of installation by a licensed HVAC or electrical contractor must be provided for a valid claim. This warranty does not cover labor, return shipping charges, or damage from improper installation or improper voltage usage. The iWave warranty begins on the date that the unit was installed. Installation of an iWave unit by any person other than a licensed HVAC or electrical contractor will void the warranty. For additional warranty questions, contact Nu-Calgon at info [at] nucalgon.com.