Water Heater Energy Efficiency Ratings

Exploring water heater options by fuel type.

Water heater energy efficiency ratings.

They use less energy than standard models saving homeowners money on their utility bills while helping protect the climate. Use the energy factor to determine the energy efficiency of a storage tankless or demand type water heater or heat pump water heater. The following is a list of water heater options by fuel or energy source. The higher the ef value is the more efficient the water heater.

Ef is determined by the department of energy s test method outlined in the 10 cfr parts 200 to 499 edition revised as of january 1 2014. The uniform energy factor for residential and certain commercial water heaters refers to its efficiency when run under standardized conditions for a 24 hour period. The energy factor ef indicates a water heater s overall energy efficiency based on the amount of hot water produced per unit of fuel consumed over a typical day. As the result of recently updated efficiency standards water heaters under 55 gallons now have a 4 percent boost in efficiency while water heaters 55 gallons or more have efficiency gains of 25.

An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters. While tankless water heaters run more efficiently than storage tank water heaters replacing a tank water heater with a tankless can be expensive and the payback time can be longer than the warranty. Efficiency standards for gas and electric water heaters are different but both use the uniform energy factor uef ratings system where higher scoring units produce more hot water while using less energy. Fuel type and its availability in your area may narrow your water heater choices.

In fact uef provides a more consistent and accurate way to measure energy efficiency performance in water heaters across all national brands. Water heaters are the second highest source of energy usage in the home. Energy star certified water heaters are an easy choice for energy savings performance and reliability. Buying a water heater.