Water Heater Energy Factor List

A heat pump water heater with an ef of 2 0 and an electricity cost of 0 0842 kwh.

Water heater energy factor list.

The new uef rating method improves the industry s ability to. Simplify the water heater selection. The typical energy factor for a gas water heater is between 0 5 and 0 7. 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. 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. Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut. 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.

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. For gas condensing water heaters the energy factor must be 0 8 or higher to qualify for the energy star label. It s important to note that energy factors can vary significantly depending on their fuel source. 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.

The uniform energy factor. You need to know or convert the unit cost of electricity by kilowatt hour kwh. Define consistent standards for measuring energy efficiency performance. Electric water heaters typically have energy factors between 0 75 and 0 95.