Water Heater Energy Factor List

The new uef rating method improves the industry s ability to.

Water heater energy factor list.

For gas condensing water heaters the energy factor must be 0 8 or higher to qualify for the energy star label. Simplify the water heater selection. 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. 365 days year x 12 03 kwh day ef x fuel cost kwh annual cost of operation.

The typical energy factor for a gas water heater is between 0 5 and 0 7. Electric water heaters typically have energy factors between 0 75 and 0 95. This means that between 75 and 95 percent of the energy used to heat the water ends up being delivered to your taps as usable hot water. Define consistent standards for measuring energy efficiency performance.

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. 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. 365 x 12 03 2 0 x 0 0842 185. As of september 1 2010 a water heater needs to have an energy factor of 0 67 or higher in order to qualify for the energy star label.

An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters. You need to know or convert the unit cost of electricity by kilowatt hour kwh. The uniform energy factor. Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut.