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National Energy Audit Tool


Heat added to the evaporating vapor to ensure that no liquid enters the compressor

Sling Psychrometer

Instrument used to measure water vapor content of the atmosphere


Approximate Leakage Area

ALA Square Inch

10% of air flow

Wet Bulb Temperature

Used to evaluate the humidity in the air


A sealed chamber at the inlet or outlet of an air handler

Dry Bulb Temperature

The temperature of air measured by a thermometer freely exposed to the air

CFM50 Per Square Foot

Flow rate at 50P divided by the total square footage


The sum of the absolute values of the supply and return static pressures


Evaporator section of the cooling system - Consists of two coils shaped like the letter "A"

Furnace fan-on temperature


Heat Rise

Supply Temp minus Return Temp

Furnace fan-off temperature



A meter that measures the flow of electrical current in amperes

Heat Exchanger

A device that transfers heat from one substance to another


Combustion Appliance Zone

Air Barrier

Material that is continuous, sealed at the seams and impermeable to airflow

Thermal Boundary

A line or plane where insulation and air barriers exist in order to resist thermal transmission and air leakage throu or within a building shell


Energy Efficient Builders Association

Sacrificial Anode

Metallic anode which is meant to be dissolved to protect other metallic components


Measure of K value of a specific material (K is a measure of heat conduction)


Lead Safe Weatherization

Flame Retention Burner

An oil burner designed to hold the flame near the nozzle surface


White powdery deposit left by water that moves through masonry and leaves minerals from mortar or soild behind as it evaporates

Rise-Run Rate for vent connectors

1/4" rise over 1' run (Allows combustion gases to rise through the vent and prevent condensation from pooling & rusting the vent)

Primary Air Barrier

When there are two air barriers the most airtight is the primary air barrier

Heating Degree Days

Degrees when average temperature is below 65F ex: average temperature today is 50F=15HDD)

1 ton of cooling

12,000 BTUs/hour


Segment of a three-dimensinal shape fabricated from a two-dimensional material (the parts of a duct elbow)

Blower Wheel

Squirrel cage wheel whose purpose is to move the air through the room


National Fenestration Rating Council


E=emissivity refers to building materials designed to reduce heat transfer through thermal conductivity

Jalousie Window

Window which consists of parrallel glass louvers set in a frame

Weep Holes

Small holes in the bottom of a window assembly that allow for water to escape


100,000 BTUs or roughly 100 cubic feet of natural gas

Rise-Run for extension ladder

1' run for every 4' rise

Dense Packing

Shoving cellulosic insulation in at a rate of 3.5-4lbs per cubic foot, usually done on exterior walls


What does propane gas do from a leak


Air Changes per Hour

Intermediate Zones

Unconditioned spaces that are sheltered within the exterior shell of the house


The arrangement of windows and doors

Latent Heat

Heat given off when matter changes state

Sensible Heat

heat that causes a change in temperature


Conduits for air travel within building cavities IE: porch overhangs

Balloon Framing

Long, continuous framing members that run from sill plate to eave line with intermediate floor structures nailed to them.

Backer Rod

Usuallly an extruded foam rod placed into voids to insulate and allow a backing for application sealant


Heat tranferred from one place to another using a fluid


Heat transfer within a substance or from one substance to another

Net free area

The actual amount of area in a vent that is not the material itself (metal grills and louvers have have 60-75% net free area, wodden ones only 20-25%)

How to fasten single wall vent pipe

3 screws or rivets


Unit of pressure measurement defined as one newton per square meter

Base Load

Water heating, lighting, refrigeration and any other year-round energy use


International Construction Code


Annual Fuel Utilization Efficiency

pocket door cavity

Where pocket cavities extend to exterior walls, shove strips of fiberglass into the door opening with a broom handle shallow enough so that door can close

Stack Effect

The movement of air into and out of a building due to indoor/outdoor air density differences and natural bouyency

Vent Connector

Connects appliances venting outlet with the chimney


American Gas Association


Continuous and unequal exchange of heat


N Factor for Missouri-one story house

Latent Heat

Energy given off when matter changes state

Energy Factor

Total energy delivered over total energy purchased expressed as a percentage


Savings to Investment Ratio

Type-L vent connector

Stainless-steel inner pipe and galvanized or black steel outer pipe


International Fuel Gas Code


Building Airflow Standard

IFGC confined space

A room containing 1 or more combustion appliances that has less than 50 cubic fee of volume for every 1000 BTU/H of appliance output

Power Venters

create a stable and negative draft, commonly used for sidewall venting


Annual Fuel Utilization Efficiency


Full Load Amp

Gas Sniffer

Electronic Combustable Gas Detector

Cold water dip tube

a plastic tube below the cold port of a water heater-carries cold water to the bottom of the tank & keeps it separated from the already-heated water at the top of the tank.


Overall heat transfer coefficient-describes how well a building element conducts heat (smaller the value the better)


Steady State Efficiency-Efficiency of a furnace once it is up and running


Total Exterior Static Pressure


Foil Scrim Kraft - foil faced batt insulation

Type-B vent

Consists of galvonized steel outer pipe and aluminum inner pipe


National Fire Protection Association

Optimal refrigerator temperature range

35-40 degrees F

Optimal freezer temp

-5 degrees F

Sensible Heat

Heat that causes a change in temperature


A loop of wire wrapped around a metal core which produces a magnetic field when electricity runs through it (usually used in switches)


Instrument used to check air pressure


Per Manufacturer's Instructions


Natural gas does what from a leak

CH4 + O2 =

C02 + H2O + CO + O2

2-4 years

Gas burner should be maintained every


Inches Water Column


the process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained to perform to design intent.

Atmospheric Chimney

Transports combustion gases using the flames' heat and gas' buoyancy

Draft Diverter

Also known as a "draft hood" helps vent combustion air away from hot water heaters


Natural Gas


Material Safety Data Sheet

Blower door standard pressure

50 Pascals

Pressure Pan

Used to block registers and measure air pressure behind it

ASHRAE 62-1989

Standard for acceptable IAQ 15 CF/M or outdoor air per person or .35 air changes per hour


Units of perceived loudness

Hours per year


Seasonal Energy Use

heating and cooling


Energy Concervation Measures


Mobile Home Energy Audit


Department of Natural Resources Energy Center


Low Income Home Energy Assistance Program


Domestic Water Heater

Dense Pack

Installation of Cellulose at density of 3.5-4.0 lbs/cubic foot

First law of thermodynamics

Energy is neither created nor destroyed, but merely moves from place to place and changes form.

Second law of thermodynamics

Heat moves from high temperature regions to low temperature regions-never the reverse


The internal heat of a material measured in BTUs per pound


Continuous spillage of combustion gases from a combustion appliance


Energy divided by time


relative humidity


A plate or strip designed to retard or redirect the flow of flue gases

capillary action

The ability of water to move through materials, even upward against gravity through small tubes or spaces

capillary barrier

A material or air space designed to stop capillary acton from carrying water into a building


Coefficient of Performance A heat pump or air conditioner's output in whatt-hours of heat moved divided by watt-hours of electrical input


one million BTU's or 10 therms


Liquid or solid material used to absorb water or water vapor


A vertical window projecting from a roof

Drainage Plane

A space that allows water storage and drainage in a wall cavity


The internal heat of a material measured in BTU's per pound


Air flowing out of a residence from its conditioned space through the shell

Fin Comb

A comb-like tool used to straighten bent fins in an air conditioner


Waterproof matterial used to prevent leakage at intersections between the roof surface at wall penetrations


A measure of light intensity

Frost Line

the maximum depth of the soil where water will freeze during the coldest weather


The triangular section of an end wall formed by the pitch of the roof


the amount of solar radiation striking a surface

Make-Up Air

Air supplied to a space to replace exhausted air


A section of pipe with multiple openings


A thick creamy stubstance used to seal seams and cracks in building materials


Oxygen Depletion Sensor

Oxygen Depletion Sensor

A safety device for unvented combustion heaters that shuts gas off when oxygen is depleted


The science of the relationship between air, water vapor, and heat


Framing members that sit on top of rafters, perpendicular to them, designed to spread support to roofing materials


A radioactive gas that decomposes into radioactive particles


The property of a material resisting the flow of electrical energy or heat energy


A movable or stationary part of a window that frames a pieces of glass


Dissolved minerals that precipitate inside boilers and storage tanks


A combustion appliance that draws combustion air from outdoors and has a sealed exhaust system


Seasonal Energy Efficiency Ratio


A bimetal switch that turns on the elements of an electric furnice in sequence


Shading Coefficient

Shading Coefficient

A decimal describing how much solar energy is transmitted through a window, compared to a clear, single glass, which has an SC of 1.0


The bottom of a window or door frame


The underside of a roof overhand or a small lowered ceiling

Solar Gain

Heat from the sun that is absorbed by a building and contributes to the need for cooling


Solar Heat-Gain Coefficient

Solar Heat-Gain Coefficient

The rato of solar heat gain through a window to incident solar heat. Includes both transmitted heat and absorbed and reradiated heat.

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