With our water heater ratings, you can cut through all the sales hype and find value. We have researched the manufacturers' data and combined that information with our years of service experience in the hvac industry to provide our unique rating system. It truly is like taking a repairman (Hvacrepairguy) with you while you shop. These reviews are for units that use electricity to heat a tank of water (at least 30 gallons) for domestic consumption. They are commonly called whole house storage water heaters.