NFI HEARTH SPECIALIST COMPREHENSIVE
ANSWERS AND QUESTIONS SET A+
✔✔Heat Loss Calculation - ✔✔calculation to determine house BTU loss; factors include
conduction through construction materials, air infiltration losses and the difference
between actual or projected outside temperatures and desired temperature inside the
house. used for determining necessary heat output from the heating appliance
✔✔Heat Output - ✔✔the amount of usable heat produced by a heating appliance;
expressed in BTU (for solid fuel and most conventional fuel appliances)
✔✔Heat Recovery Ventilator (HRV) - ✔✔mechanical system that uses blowers and an
air to air heat exchanger to replace indoor air with preheated outdoor air
✔✔Heat Value - ✔✔Amount of heat potential of one cubic foot of gas when burned. also
known as caloric value
✔✔Higher Heating Value (HHV) - ✔✔the amount of heat released by a specific quantity
of fuel after it is combusted and the products have returned to their pre-combustion
temperature, which includes the latent heat of vaporization of water in the combustion
products (the heat from combustion produced water is recovered)
✔✔Hip Roof - ✔✔a roof that rises by inclined planes from all four sides of a building
✔✔Hot Air Plenum - ✔✔sheet metal chamber around mounted to the furnace, into
which hot air is directed, and to which ducts are attached for hot air distribution into the
house
✔✔Hot Junction - ✔✔joined, heated end of thermocouple/thermopile
✔✔Hot Surface Igniter - ✔✔type of electronic ignition system in which a flow bar is
heated by electrical means to a temperature of about 2,500 degrees Fahrenheit to
provide the heat to ignite main burner gas
,✔✔House Pressure Test - ✔✔a process to determine the level of depressurization
within a residential structure under different conditions, including during use of exhaust
devices. results used in the hearth industry to determine whether maximum
depressurization levels exceed spillage resistance pressure of hearth systems
✔✔Hybrid Woodstove - ✔✔a solid fuel appliance with dedicated air passages for the
combustor, but also with separated dedicated air passages for secondary air
combustion (as in non-catalytic stoves). designated by EPA as a catalytic woodstove
✔✔Ignition Temperature - ✔✔the lowest temperature at which combustion occurs.
varies widely with reference to the variety of flammable gases spontaneously
combusting in a solid fuel appliance
✔✔Increaser - ✔✔chimney connector component that permits the transition from
smaller to larger connector, thimble, liner, or chimney
✔✔Infrared Radiation - ✔✔waves of light energy, beyond the visible part of the
spectrum, that transfer heat energy and are converted to sensible heat when they strike
a solid object
✔✔Intermittent Ignition System - ✔✔means of lighting the pilot or main burner without
the use of a standing pilot, by electronic spark or hot surface ignition. also known as
electronic ignition device
✔✔International Fuel Gas Code - ✔✔a standard for the installation of gas appliances,
piping, and venting
✔✔Ignition Systems - ✔✔devices that ignite the pilot burner and/or the main burner
assembly
✔✔Ignition Temerature - ✔✔the temperature at which combustion of a substance
begins
✔✔Incomplete Combustion - ✔✔improper air/fuel mixture or inadequate temperatures
resulting in less than complete burning of fuel. may produce aldehydes an/or carbon
monoxide
✔✔Joint Compounds - ✔✔non-hardening materials used on pipe threads to insure a
proper seal
✔✔Joist - ✔✔parallel framing member installed horizontally to support floor and ceiling
loads
, ✔✔Labeled - ✔✔equipment or material identified as having undergone approved
inspection and compliance manufacturing and performance procedures
✔✔Latent Heat of Water - ✔✔the quantity of heat released (or absorbed) by a
substance undergoing a change of state, such as ice changing to water or water to
steam
✔✔Lath - ✔✔a building material of narrow wood, metal, gypsum, or insulating board
that is fastened to the frame of a building to act as a base for plaster, shingles, or tiles
✔✔Leakage Testing - ✔✔procedure to ensure that there is no uncontrolled flow of fuel
gas in the gas piping system and/or the appliance
✔✔Lifting Flames - ✔✔an unstable burner condition in which flames rise above or blow
off the burner port
✔✔Limit Switch - ✔✔Bimetallic device set to react to excessive temperature by causing
gas flow to be cut off
✔✔Lintel - ✔✔a horizontal structure member that supports the load over an opening
such as a door or window
✔✔Liquefied Petroleum Gas (LPG) - ✔✔colorless, odorless, and non-toxic gas
separated from wet natural gas, light crude oil, and oil refinery gases. composed
predominately of following hydrocarbons or mixtures thereof: propane, propylene,
normal butane or isobutane and butylene
✔✔Listed - ✔✔equipment or materials tested to required standards by a testing
organization and usually included in a list published by a model code authority that
indicates that the equipment meets applicable inspection and testing procedure
standards. assures suitability for use in a specified manner when equipment installed in
accordance with the manufacturer's installation instructions
✔✔Loadbearing Wall - ✔✔a wall that supports structural weight above it. it supports
overlapped or butted ceiling or floor joists running above it
✔✔Lower Heating Value (LHV) - ✔✔the amount of heat released by a specific quantity
of fuel after it is combusted and returned to a temperature above the condensation point
of water vapor, which assumes that the latent heat of vaporization of combustion
produced water is not recovered
✔✔Main Gas Burner - ✔✔device for the final conveyance of gas or a mixture of gas and
air to the combustion zone. consists of burner orifice, air shutter, mixer, and burner
head
ANSWERS AND QUESTIONS SET A+
✔✔Heat Loss Calculation - ✔✔calculation to determine house BTU loss; factors include
conduction through construction materials, air infiltration losses and the difference
between actual or projected outside temperatures and desired temperature inside the
house. used for determining necessary heat output from the heating appliance
✔✔Heat Output - ✔✔the amount of usable heat produced by a heating appliance;
expressed in BTU (for solid fuel and most conventional fuel appliances)
✔✔Heat Recovery Ventilator (HRV) - ✔✔mechanical system that uses blowers and an
air to air heat exchanger to replace indoor air with preheated outdoor air
✔✔Heat Value - ✔✔Amount of heat potential of one cubic foot of gas when burned. also
known as caloric value
✔✔Higher Heating Value (HHV) - ✔✔the amount of heat released by a specific quantity
of fuel after it is combusted and the products have returned to their pre-combustion
temperature, which includes the latent heat of vaporization of water in the combustion
products (the heat from combustion produced water is recovered)
✔✔Hip Roof - ✔✔a roof that rises by inclined planes from all four sides of a building
✔✔Hot Air Plenum - ✔✔sheet metal chamber around mounted to the furnace, into
which hot air is directed, and to which ducts are attached for hot air distribution into the
house
✔✔Hot Junction - ✔✔joined, heated end of thermocouple/thermopile
✔✔Hot Surface Igniter - ✔✔type of electronic ignition system in which a flow bar is
heated by electrical means to a temperature of about 2,500 degrees Fahrenheit to
provide the heat to ignite main burner gas
,✔✔House Pressure Test - ✔✔a process to determine the level of depressurization
within a residential structure under different conditions, including during use of exhaust
devices. results used in the hearth industry to determine whether maximum
depressurization levels exceed spillage resistance pressure of hearth systems
✔✔Hybrid Woodstove - ✔✔a solid fuel appliance with dedicated air passages for the
combustor, but also with separated dedicated air passages for secondary air
combustion (as in non-catalytic stoves). designated by EPA as a catalytic woodstove
✔✔Ignition Temperature - ✔✔the lowest temperature at which combustion occurs.
varies widely with reference to the variety of flammable gases spontaneously
combusting in a solid fuel appliance
✔✔Increaser - ✔✔chimney connector component that permits the transition from
smaller to larger connector, thimble, liner, or chimney
✔✔Infrared Radiation - ✔✔waves of light energy, beyond the visible part of the
spectrum, that transfer heat energy and are converted to sensible heat when they strike
a solid object
✔✔Intermittent Ignition System - ✔✔means of lighting the pilot or main burner without
the use of a standing pilot, by electronic spark or hot surface ignition. also known as
electronic ignition device
✔✔International Fuel Gas Code - ✔✔a standard for the installation of gas appliances,
piping, and venting
✔✔Ignition Systems - ✔✔devices that ignite the pilot burner and/or the main burner
assembly
✔✔Ignition Temerature - ✔✔the temperature at which combustion of a substance
begins
✔✔Incomplete Combustion - ✔✔improper air/fuel mixture or inadequate temperatures
resulting in less than complete burning of fuel. may produce aldehydes an/or carbon
monoxide
✔✔Joint Compounds - ✔✔non-hardening materials used on pipe threads to insure a
proper seal
✔✔Joist - ✔✔parallel framing member installed horizontally to support floor and ceiling
loads
, ✔✔Labeled - ✔✔equipment or material identified as having undergone approved
inspection and compliance manufacturing and performance procedures
✔✔Latent Heat of Water - ✔✔the quantity of heat released (or absorbed) by a
substance undergoing a change of state, such as ice changing to water or water to
steam
✔✔Lath - ✔✔a building material of narrow wood, metal, gypsum, or insulating board
that is fastened to the frame of a building to act as a base for plaster, shingles, or tiles
✔✔Leakage Testing - ✔✔procedure to ensure that there is no uncontrolled flow of fuel
gas in the gas piping system and/or the appliance
✔✔Lifting Flames - ✔✔an unstable burner condition in which flames rise above or blow
off the burner port
✔✔Limit Switch - ✔✔Bimetallic device set to react to excessive temperature by causing
gas flow to be cut off
✔✔Lintel - ✔✔a horizontal structure member that supports the load over an opening
such as a door or window
✔✔Liquefied Petroleum Gas (LPG) - ✔✔colorless, odorless, and non-toxic gas
separated from wet natural gas, light crude oil, and oil refinery gases. composed
predominately of following hydrocarbons or mixtures thereof: propane, propylene,
normal butane or isobutane and butylene
✔✔Listed - ✔✔equipment or materials tested to required standards by a testing
organization and usually included in a list published by a model code authority that
indicates that the equipment meets applicable inspection and testing procedure
standards. assures suitability for use in a specified manner when equipment installed in
accordance with the manufacturer's installation instructions
✔✔Loadbearing Wall - ✔✔a wall that supports structural weight above it. it supports
overlapped or butted ceiling or floor joists running above it
✔✔Lower Heating Value (LHV) - ✔✔the amount of heat released by a specific quantity
of fuel after it is combusted and returned to a temperature above the condensation point
of water vapor, which assumes that the latent heat of vaporization of combustion
produced water is not recovered
✔✔Main Gas Burner - ✔✔device for the final conveyance of gas or a mixture of gas and
air to the combustion zone. consists of burner orifice, air shutter, mixer, and burner
head
