Water Heater Efficiency Calculation

Please remember that the calculators above assume 100 conversion efficiency.

Water heater efficiency calculation.

Small storage water heaters tank type. Range in size from 2 5 to 19 gallons. To calculate a water heater s energy factor you take the amount of energy the water heater puts to use and divide it by the total amount of energy that goes into powering the unit. For the base case where can i get these numbers from.

Lifetime energy cost is the sum of the discounted value of the annual energy costs based on assumed water heater life of 13 years. The water heaters themselves haven t changed but the way we calculate the ratings and other facts and figures associated with them is different. Tiny point of use pou electric storage water heaters with capacities ranging from 8 to 32 liters 2 to 6 gallons. Instantaneous water heaters tankless type.

If you haven t yet considered what type of water heater might be best for your home learn more about selecting a new water heater. Most tankless units can provide up to 3 5 gallons of heated water per minute. Input specific heat btu output gph x 8 25 lbs gal. Performance requirements for water heating equipment i am trying to calculate water heating equipment it looks like that i should have the ef et and sl as per description below the table 7 8 of 90 1 2007.

2 the number of high efficiency gas storage water heaters available on the market is sufficient although lower in comparison to the typical conventional gas storage water heaters at the federal standard. What is a water heater s energy factor. Future electricity price trends and a discount rate of 3 2 are based on federal guidelines. Rise x 1 0 btu hr.

High efficiency gas storage water heaters account for an estimated 350 000 residential sales per year. In fact uef provides a more consistent and accurate way to measure energy efficiency performance in water heaters across all national brands. Also the calculator is only correct in the theoretical case that while the water is being heated no heat escapes from the water to the environment air or walls etc. Various formulas for water heating calculations efficiency gph x 8 25 x temp.

For sizing combination water and space heating systems including some heat pump systems and tankless coil and indirect water heaters consult a qualified contractor. Energy factor ef and thermal efficiency et are minimum. For an electrical heater that can be a good assumption but not for a gas heater.