Page 348

NORA Oilheat Technicians Manual

Electron: A negatively charged particle of matter. Energy: The ability or capacity to do work. Fahrenheit: A thermometer scale at which the freezing point of water is 32°F and its boiling point is 212°F above zero. It generally used in the United States for expressing temperature. Flame Velocity (Rate of Flame Propagation): is the speed with which a flame travels through a given fuel-air mixture. It varies with the fuel, fuel-air mixture ratio and temperature of the mixture. Flash Point: Maximum temperature at which fueloil can be safely stored and handled without serious fire hazard. ASTM minimum for No.1 and No.2 is 100°F). Flue Gas: Includes all gases which leave the furnace combustion chamber by way of a flue. Flue gas consists of nitrogen, gaseous products of combustion, water vapor and oxygen. Frequency: The number of complete cycles per second existing in any form of wave motion; such as the number of cycles per second of an alternating current. Fuel: May be defined as any substance, solid, liquid or gaseous, which may be relatively easily ignited and burned to produce heat. Practically all fuels consist of carbon and hydrogen. Furnace: That part of a boiler or warm air heating plant in which combustion takes place. Sometimes it is also the complete heating unit of a warm air heating system. Gauge Pressure: The pressure above that of the atmosphere. It is the pressure indicated on an ordinary pressure gauge. It is expressed as a unit pressure such as pounds persquare inch (PSI) gauge. Generator: A machine that converts mechanical energy into electrical energy. Grille: A perforated covering for an air inlet or outlet usually made of wire screen, cast iron or other material. Gross Heating Value: Is the total amount of heat produced by the complete combustion of the fuel at atmospheric conditions. Ground: A metallic connection with the earth to establish ground potential. Also a common return to a point of zero potential. Heat: That form of energy into which all other forms may be changed. Heat always flows from a body of higher temperature to a body of lower temperature. Heat of Combustion: The heat evolved when the substance combines rapidly with oxygen. Heat Exchanger: Any device which is used for transferring energy from one fluid or gas to another. Heat Unit: In the foot-pound-second system: the British Thermal Unit (BTU): in the centimetergram-second system: the calorie (cal). Heating Medium: A substance such as water, steam, or air used to convey heat from the boiler, furnace, or other source of heat to the heating units from which the heat is dissipated. Hot Water Heating System: A heating system in which water is used as the medium by which heat is carried through pipes from the boiler to the heating units. Humidistat: An instrument which controls the relative humidity of the air in a room. Humidity: The amount of water vapor within a given space, generally measured in pounds-per-cubic foot. Hydronics: The science of heating and cooling with water. Ignition: The act of starting combustion. Ignition Point: Lowest temperature at which rapid combustion of a fuel will take place in air. For No.2 oil, the ignition point is over 500°F. Insulation: A material which is used to minimize the heat losses from a given space. Kilowatt Hour: It is 1000 Watts per hour of electrical energy and is equivalent to 3,412 BTU. Latent Heat: The energy involved to change the physical state of a substance, (from a liquid to a gas) without changing its temperature. Magnetic Field: The space in which a magnetic force exists. Master Control: See “primary control.” Milliammeter: An ammeter that measures current in thousands of an ampere. Nitrogen (N2): Is present in air in a large quantity and does not serve any purpose in the process of combustion. Ohm: The unit of electrical resistance. Ohmmeter: An instrument for directly measuring resistance in ohms. Glossary X—Oilheat Technicians Manual


NORA Oilheat Technicians Manual
To see the actual publication please follow the link above