Dort is Reliance.http://www.reliancewaterheaters.com/prod/elec.html
6-50 Dort is 606 series
Your Customer wants energy factor.
Pdf below shows energy factor for 606 series:http://www.reliancewaterheaters.com/lit/spec/electric/R606E0510.pdf
55 gallon has .90 energy factor.
4500 watt water heater costs about $48 per month with electric prices at 12 cents per Kwhhttp://waterheatertimer.org/Figure-Volts-Amps-Watts-for-water-heater.html
Read about energy factor:http://www.energysavers.gov/your_home/water_heating/index.cfm/mytopic=13000
"...energy efficiency based on the amount of hot water produced per unit
of fuel consumed over a typical day. This includes the following:
Recovery efficiency - how efficiently the heat from the energy source is transferred to the water
Standby losses - the percentage of heat loss per hour from the stored
water compared to the heat content of the water (water heaters with
Cycling losses - the loss of heat as the water circulates through a water heater tank, and/or inlet and outlet pipes." end quote
Energy factors exist so large appliances can be compared to small appliances.
-This is like comparing aircraft-carriers to small ships.
-The purpose is so large gigantic appliances look like reasonable energy alternatives, when that is not actually true.
-The aircraft carrier could have better efficiency number than smaller ship, and it gives misleading appearance that aircraft-carrier will save the consumer money. Many of the super high-consumption 80 gallon water heaters have higher energy factor, but they consume huge amounts of energy each time operated. Simple Dort series is a better value even with lower efficiency number.
-The efficiency number is only for a new product. There is no measure showing how long that product will maintain the efficiency rating.
-And lastly, the manufacturer is putting energy factor on the product, like writing your own performance review, so who can possibly double-check the energy factor.