The two figures are related but different.
Water heater energy factor vs efficiency.
Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut.
Most new water heaters have an efficiency factor ef of 58 60.
A water heater s energy factor ef is a measure of useful energy coming out of the water heater divided by the amount of energy going in.
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.
That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat.
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 term is used by the united states department of energy to develop and enforce minimum energy conservation standards under.
An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters.
The greater the energy factor the more efficient the appliance is.
That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat.
An energy factor is a metric used in the united states to compare the energy conversion efficiency of residential appliances and equipment.
Energy factor is a measure of efficiency for a variety of appliances including water heaters.
Energy factor calculates the amount of energy delivered as hot water compared to the energy consumption of a residential water heater over a 24 hour period.
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.
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.
Just 15 of the nation s 4 7 million gas water heater shipments were high efficiency gas storage water heaters with an energy factor of 0 62 instead of conventional models with an energy factor at the federal standard the aggregate energy savings would amount to 13 4 million therms per year.
The following is a list of water heater options by fuel or energy source.
The new uef rating method improves the industry s ability to.
Simplify the water heater selection.
Exploring water heater options by fuel type.
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 energy factor is currently used for rating the efficiency of water heaters dishwashers clothes washers and clothes dryers.
Fuel type and its availability in your area may narrow your water heater choices.
On the contrary thermal efficiency is the amount of energy delivered as heated water compared to the energy consumption of the water heater.