The higher the ef value is the more efficient the water heater.
Water heater energy factor vs efficiency.
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.
That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat.
Exploring water heater options by fuel type.
That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat.
The following is a list of water heater options by fuel or energy source.
The greater the energy factor the more efficient the appliance is.
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.
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.
An energy factor is a metric used in the united states to compare the energy conversion efficiency of residential appliances and equipment.
The two figures are related but different.
Fuel type and its availability in your area may narrow your water heater choices.
Define consistent standards for measuring energy efficiency performance.
The new uef rating method improves the industry s ability to.
Most new water heaters have an efficiency factor ef of 58 60.
An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters.
The energy factor is currently used for rating the efficiency of water heaters dishwashers clothes washers and clothes dryers.
On the contrary thermal efficiency is the amount of energy delivered as heated water compared to the energy consumption of the water heater.
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 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.
Simplify the water heater selection.
Use the energy factor to determine the energy efficiency of a storage tankless or demand type water heater or heat pump water heater.
The uniform energy factor.
Energy factor is a measure of efficiency for a variety of appliances including water heaters.
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.
Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut.