- 1 What is an EF rating on a water heater?
- 2 What is the difference between EF and UEF?
- 3 What is DOE Energy Factor?
- 4 What is uniform energy factor for hot water heaters?
- 5 What is the first hour rating of a water heater?
- 6 How many gallons should my water heater be?
- 7 What is a good UEF for water heater?
- 8 Are new electric water heaters more efficient?
- 9 How do I know what UEF my water heater is?
- 10 What is a good energy factor?
- 11 What type of factor is energy?
- 12 What does L kWh mean?
- 13 What is a good first-hour rating?
- 14 How long do water heaters last?
- 15 What is water heater efficiency?
What is an EF rating on a water heater?
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. This includes the following: Recovery efficiency – how efficiently the heat from the energy source is transferred to the water.
What is the difference between EF and UEF?
Previously, you may have seen efficiency measured by Energy Factor (EF). UEF replaces this metric. A higher UEF means a water heater is more energy efficient and will cost less to operate compared to other water heaters in the same bin. A water heater’s UEF can only be compared with water heaters within the same bin.
What is DOE Energy Factor?
The energy factor (EF) is used to rate the efficiency of gas-fired (natural gas) or oil-fired water heaters. It is the amount of energy supplied as hot water divided by the total amount of energy used by the water heater over a 24-hour (hr) period. A lower standby loss indicates higher efficiency.
What is uniform energy factor for hot water heaters?
Uniform Energy Factor (UEF): The newest measure of water heater overall efficiency. The higher the UEF value is, the more efficient the water heater. UEF is determined by the Department of Energy’s test method outlined in 10 CFR Part 430, Subpart B, Appendix E.
What is the first hour rating of a water heater?
The first hour rating is the number of gallons of hot water the heater can supply per hour (starting with a tank full of hot water).
How many gallons should my water heater be?
But if you only need a loose estimate of what size you need (versus an exact calculation), follow these guidelines: For 1 to 2 people: 30-40 gallons. For 2 to 3 people: 40-50 gallons. For 3 to 4 people: 50-60 gallons.
What is a good UEF for water heater?
Uniform Energy Factor (UEF) rating In general, ENERGY STAR certified conventional gas and electric water heaters have UEF ratings between 0.65 and 0.95 — or 65 to 95 cents on the dollar — while hybrid electric heat pump water heaters have much higher UEF ratings of 2.75 to 3.5.
Are new electric water heaters more efficient?
New efficient water heaters can help reduce this excess heat loss. All other things being equal, the smaller the water heater tank, the higher the efficiency rating. A new electric water heater uses about 10 times more electricity than an average new refrigerator!
How do I know what UEF my water heater is?
UEF ratings are determined by assigning water heaters into one of four different categories of hot water usage and then evaluating their performance based on that usage. These categories are called bins. A water heater is assigned a UEF within its bin based upon its first hour rating.
What is a good energy factor?
If you’re going to buy an electric water heater, we suggest you look for one with an Energy Factor equal to. 93 or greater. This represents a 5 to 10 percent savings compared to a standard efficiency electric water heater.
What type of factor is energy?
INDUSTRY AND BUSINESS, ENERGY AS A FACTOR OF PRODUCTION IN. The production of goods and services requires energy as an input, which is called a factor of production. Energy sources vary in their effectiveness as a factor of production, depending on their energy characteristics.
What does L kWh mean?
The energy efficiency of dehumidifiers is measured by its energy factor, in liters of water removed per kilowatt-hour (kWh) of energy consumed or L/kWh. In general, a higher energy factor means a more efficient dehumidifier.
What is a good first-hour rating?
For the majority of homes, peak hot water use is in the morning when people are showering. This number is used to determine the best first-hour rating. So if your peak hour demand is 40 gallons, the best match for a water heater would have a first-hour rating of 38 to 42 gallons.
How long do water heaters last?
How Long Do Water Heaters Last? Based on the manufacturer’s suggested service life, the life expectancy of a water heater is about eight to 12 years. That varies with the location and design of the unit, quality of installation, maintenance schedule and water quality.
What is water heater efficiency?
Heat pump water heaters are highly efficient and use 30% of the energy of a conventional electric hot water system. These systems use a refrigeration cycle to extract heat from the air to heat the water.