Term Term Definition Options Unit of Measure
Natural Ventilation Metric

Metric used in measuring the rate of natural ventilation

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Natural Ventilation Rate

Average rate of natural ventilation when used. Units depend on ventilation method

View Unknown
Number Of Discrete Cooling Stages

The number of discrete operating stages, excluding "off."

View count
Number Of Discrete Fan Speeds

The number of discrete operating speeds for the supply-fan motor, excluding "off." Only used if flow control is "stepped"

View count
Number of Heating Stages

The number of heating stages, excluding "off."

View count
Other HVAC Type

Type of space conditioning equipment that is not classified as heating, cooling, or air-distribution. This category includes ventilation, dehumidification, humidification, and air cleaning systems.

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Output Capacity

Output capacity of equipment.

View MMBtu
Part Load Ratio Below Which Hot Gas Bypass Operates

The part load ratio of a chiller below which hot gas bypass (HGBP) operates.

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Pipe Application

Application of pipe

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Pipe Configuration

Number of pipes for distributing steam, refrigerant, or water to individual zones.

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Pipe Insulation Thickness

Defines how thick insulation on pipes in a heating, cooling, water heating system is.

View in
Pipe Location

Percentage of pipe length in conditioned space

View percent

The type of refrigerant used in the heat pump

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Refrigerant Charge Factor

Used to adjust cooling efficiency for assumed slightly degraded performance if refrigerant charge is not verified through acceptance test procedures

View percent
Reheat Source

Energy source used to provide reheat energy at a terminal unit.

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Required Ventilation Rate

Minimum ventilation rate required by local code.

View cfm
Return Duct Percent Conditioned Space

Percentage of return duct surface area, including the air handler, that is located within conditioned space (0-1).

View percent

Sequencing availability of HVAC system

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Static Pressure

The expected or installed internal static pressure of the system at full supply fan speed including all filters, coils, and accessories.

View Pa
Supply Duct Percent Conditioned Space

Percentage of supply duct surface area that is located within conditioned space (0-1).

View percent
Supply Fraction Of Duct Leakage

Fraction of total duct leakage that is on the supply side. Remainder is assumed to be on the return side (0-1).

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System Performance Ratio

Ratio of annual system load to the annual system energy consumption (similar to a whole system COP). A higher value indicates less heating and/or cooling energy use to meet the loads, and therefore represents a more efficient HVAC system. SPR can be used to describe the heating, cooling, and overall HVAC systems.

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Ventilation Rate

Installed flow rate for mechanical ventilation system.

View cfm
Ventilation Type

Type of ventilation, and use of heat recovery

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Water Side Economizer

Presence of water-side economizer to provide free cooling.

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