Beginning june 12 2017 ef ratings will be replaced with the new industry standard for measuring energy efficiency in water heaters called uniform energy factor uef.
Water heater energy factor ratings.
Use the energy factor to determine the energy efficiency of a storage tankless or demand type water heater or heat pump water heater.
Define consistent standards for measuring energy efficiency performance.
For example an electric heat pump water heater typically is more energy efficient than an electric conventional storage water heater.
Simplify the water heater selection.
They heat your water just like standard models but with much less energy saving you up to 3500 over a unit s lifetime.
Simplify the water heater selection.
These categories are called bins.
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.
An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters.
The type of water heater you choose will also affect your water heating costs.
A water heater that generates more hot water while requiring less energy to power the unit will have a higher ef rating.
A water heater s uef can only be compared with water heaters within the same bin.
Beginning june 12 2017 ef ratings will be replaced with the new industry standard for measuring energy efficiency in water heaters called uniform energy factor uef.
The higher the ef value is the more efficient the water heater.
Define consistent standards for measuring energy efficiency performance.
A water heater is assigned a uef within its bin based upon its first hour rating.
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.
The new uef rating method improves the industry s ability to.
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 new uef rating method improves the industry s ability to.
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.
Buying a water heater.
A higher uef means a water heater is more energy efficient and will cost less to operate compared to other water heaters in the same bin.
Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut.