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Definitions for Column Headers- Whole-Home Gas Tankless Water Heaters Product List



Brand and Model
This is how a particular water heater is identified. Manufacturers identify products they produce using the brand and model number. Some products may also be identified with a name or SKU, which is different from the brand or model number. You should always be able to find the brand and model number on a product.

Model numbers sometimes contain wildcard characters, such as *, #, and X, that are placeholders for non-energy attributes, such as color.

Fuel Type
Fuel type refers the kind of fuel the water heater uses to heat the water, either natural gas or propane.

Location
Options for mounting the tankless water heater in the home: indoor, outdoor, or both.

Height (inches)
Vertical height of the tankless unit.

Width (inches)
Horizontal width of the tankless unit.

Depth (inches)
Depth of the tankless unit measured from the wall.

Max Input (Thousand BTU per hour)
Input refers to the burner size of the water heater, in thousand BTU per hour. This is the highest setting for the unit.

Energy Factor (EF)
Energy Factor is the ratio of useful energy output from the water heater to the total amount of energy delivered to the water heater. EF is a metric used to compare relative efficiencies of water heaters. The higher the EF is, the more efficient the water heater. EF is determined by the DOE test procedure, Code of Federal Regulations, Title 10, Section 430.

Therms/year (Gas)
Therms/year refers to the amount of natural gas consumed by the water heater according to its Energy Factor determined by the DOE test procedure, Code of Federal Regulations, Title 10, Section 430.

Gallons/year (Propane)
Gallons/year refers to the amount of propane consumed by the water heater according to its Energy Factor determined by the DOE test procedure, Code of Federal Regulations, Title 10, Section 430.

Min Gallons Per Minute
The minimum amount of water required to activate the burner.

Max Gallons Per Minute
The maximum amount of hot water the unit is sized to deliver per minute over a 77�F temperature rise.

Recovery Efficiency
Recovery efficiency refers to how efficiently the heat from the burner is transferred to the water in the tank.

Min Warranty � Heat Exchanger (years) and Min Warranty - Parts (years)
Warranty is an assurance by the manufacturing partner that the purchased equipment (heat exchanger) and components (parts) are warranted for a certain required period-of-time, depending on the technology. Minimum warranty is the shortest warranty you can receive on the qualified water heater model.

Active
Models that appear in parenthesis and in red are discontinued by manufacturers, but may still be available in stores. Discontinued models will appear on this list for a year after their last production date to allow retailers to clear inventory. These models are still ENERGY STAR qualified, but they are no longer manufactured. Sponsors, such as utilities, may honor incentives for discontinued models at their discretion.