Article Index

NOx- Produced from the reaction of nitrogen and oxygen gases in the air during combustion, especially at high temperatures. Abbreviation for all of the family of oxides of nitrogen.

Nozzle- Is a short flanged or welded neck connection on a drum or shell to control direction of fluids into or out of.

Oil burner- Is a mechanical device that combines fuel oil with proper amounts of air before delivering the mixture to the point of ignition in a combustion chamber.

Oil gun- Part of a burner’s assembly that atomizes oil into a fine spray so it can be blown into the combustion chamber.

Oil tip- The part of the oil gun that blows the atomized oil fuel mixture into the furnace.

Oil heat and pumping set- Parts of a heater for warming fuel oil to yield the desired viscosity, and a pump for delivering the oil at the desired pressure.

Operating control- Is a burner management control to start and stop the burner and must be set below the high limit control.

Operating pressure- The pressure registered on a gauge when a system is in normal operation.

Orsat- Is a gas analyzer which is a piece of laboratory equipment used to analyze a gas sample (typically fossil fuel flue gas) for its oxygen, carbon monoxide and carbon dioxide content.

Overpressure- Excessive pressure applied and is dangerous to operate above the safe operating pressure.

Oxidation- Is the interaction between oxygen molecules and other substances.

Oxidizing atmosphere- Refers to a gaseous atmosphere in which an oxidation reaction occurs.

Oxygen attack- Oxygen in water produces pitting and corrosion.

Packaged boiler- A boiler supplied with all needed components including; burner, controls and auxiliary equipment, designed as a single engineered package, and ready for on-site installation.

Pass- Confined passage that contains a heating surface which fluid flows through in one direction typically.

Perfect combustion- The complete oxidation of all the combustible constituents of a fuel, utilizing all the oxygen supplied.

pH- Is a measure of the hydrogen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have a low pH and solutions with a low concentration of H+ ions have a high pH.

Pilot (Ignitor)- A flame utilized to ignite the fuel at the main burner or burners.

Pitot tube- Is a pressure measurement instrument used to measure gas flow stream velocity.

Pitting- Is a form of extremely localized corrosion from an oxygen attack that leads to the creation of small holes in the metal of a boiler.

Port- An opening allowing the oils, slime and other floatable debris to pass through.

Postpurge- A method of scavenging the furnace and boiler passes to remove all combustible gases after flame failure controls have sensed pilot and main burner shutdown and safety shut-off valves are closed.

Power burner- A forced air burner controls the mixture of gas and air that is injected into the boiler's combustion chamber overcoming any resistance to deliver the quantity of air required for combustion.

ppm- Abbreviation for parts per million.

Precipitate- Is an insoluble solid that emerges from a liquid solution. To separate materials from a solution by the formation of insoluble matter by chemical reaction. The material which is removed.

Precipitation- Is the creation of a solid in a solution or inside another solid during a chemical reaction or by diffusion in a solid the removal of solid or liquid particles from a fluid.