The Hybrid Electric heat pump water heater from American is the most cost effective energy-efficient option available for consumers who want to save money on their utility bills.How Do They Work?Absorb ambient heat from the surrounding air to heat water using a compressor and environmentally-friendly R134a refrigerantSelf-contained heat pump unit is integrated into the top of the tankMultiple operating modes to maximize efficiency and performance Features:ENERGY STAR qualifiedMeets NEEA Tier 3 of the Advanced Water Heater Specification (Price subject to change without notice. Check stock before order)