Water Heater Energy Factor Vs Efficiency

Simplify the water heater selection.

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. An older measure of water heater overall efficiency that is being phased out due to new test methods for water heaters. The following is a list of water heater options by fuel or energy source. 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 greater the energy factor the more efficient the appliance is. Energy factor is a measure of efficiency for a variety of appliances including water heaters. An energy factor is a metric used in the united states to compare the energy conversion efficiency of residential appliances and equipment. The term is used by the united states department of energy to develop and enforce minimum energy conservation standards under.

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. The energy factor is currently used for rating the efficiency of water heaters dishwashers clothes washers and clothes dryers. 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. That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat.

On the contrary thermal efficiency is the amount of energy delivered as heated water compared to the energy consumption of 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. Define consistent standards for measuring energy efficiency performance. 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 fuel used by a water heating system will not only affect annual operation costs but also the water heater s size and energy efficiency. Use the energy factor to determine the energy efficiency of a storage tankless or demand type water heater or heat pump water heater. Fuel type and its availability in your area may narrow your water heater choices.

The two figures are related but different. The uniform energy factor. That means that 58 60 of the energy that is being used to heat your water is effectively converted into heat. The higher the ef value is the more efficient the water heater.

Exploring water heater options by fuel type.