Emissions Testing on Boilers
What is a boiler?
A boiler is a pressurized receptacle that supplies a heat transfer surface (typically via a series of tubes) connecting the combustion products and the water. Boilers are incredibly strong, as they must withstand the pressure created within.
The boiler is the most essential part of some central heating systems, where natural gas courses into the combustion chamber and is ignited. The natural gas is then carried to the heat exchanger that connects to a pipe carrying cold water, which the heat exchanger then heats to a range from 140-195 degrees, depending on the system.
The water courses through pipes in your building, through the radiators, and is then carried back to the boiler, and in this process has cooled considerably. The water in the pipes creates warmth in your home or building. The boiler must continuously fire so that the water stays hot enough to deliver heat.
To be concise, the objective of a boiler is to generate hot water or steam to heat industrial buildings or dwelling homes.
What is a boiler used for?
In a dwelling or building, boilers are used to generate hot water that in turn is used to provide central heat to a dwelling or structure. The generation component of a steam system uses a boiler to add energy to a feedwater supply to produce steam. The energy is delivered from the combustion of fossil fuels or from byproduct refuse heat.
The same water is contained in the system forever (it may be removed for maintenance purposes) and recirculated to heat the building.
Steam boilers are used for more industrial purposes such as industrial heating implementations and turbines used for power generation, while water boilers are used for housing.
How do boilers work?
Boilers supply radiant heat. The emissions that are of concern to environmental agencies and regulators occur when oxygen in the air and the hydrogen and carbon in the fuel are amalgamated to oxidize in the combustion operation ending with heat and carbon dioxide (CO2) and vaporized water (H20). In normal applications, Nitrogen oxides (NOx) and carbon monoxide (CO) are the product.
This means that, in contrast to forced air heat from a furnace, objects in a room are heated. With boiler-supplied radiant heat, articles in a dwelling or building absorb heat at a much faster rate than forced air heat. This makes boiler heat more energy-efficient and cost-effective because thermostats can be set at a lower temperature and left off for longer periods.
Boilers are often a preferred source of heat because of this cost-effectiveness, and they offer a more steady heat in the home.
Your boiler should be cleaned every year by a professional boiler cleaning company, ensuring that the boiler works smoothly, and there is no downtime.
Dwellings or buildings that have boilers with a maximum design temperature input rating of 10 to 100 million BTU per hour that were manufactured or refurbished since June of 1989 must maintain certain standards laid out by the federal government in the New Source Performance Standards.
Most dwellings and buildings use natural gas for boiler power, and in some cases, propane. The foremost controlled emissions are NOx, CO, CO2, and particulate matter which is of concern as they are harmful to the environment as well as to human health.
What emissions are controlled?
The following emissions created by a boiler’s combustion are controlled by various regulatory authorities:
Carbon Monoxide (CO): Carbon monoxide is produced with incomplete combustion. A well made and thoroughly maintained and cleaned boiler will reach absolute combustion so that the fuel reaches maximum energy release. Carbon molecules look for oxygen molecules and if they do not find any, they will change into carbon monoxide (CO). Note: most boilers have a mechanism designed to limit the production of carbon monoxide.
Reason for emission control: Carbon monoxide is poisonous as a gas, and is one of the major causes of climate change. As a solid, carbon monoxide is soot. Soot is filthy and hazardous to the environment.
Nitrogen Oxides (commonly known as NOx): NOx gases are produced during combustion, and form when fuel is burned at high temperatures. The air that we breathe in the atmosphere is composed of 21% oxygen, 78% nitrogen, and 1% other gases such as greenhouse gases, neon, ozone, hydrogen, and nitrous oxide, among others. NOx is created by the reaction of nitrogen and oxygen and then a reaction with atmospheric air in the course of the combustion of fuels, frequently under high temperatures (car engines, boilers). Boilers that use oil for fuel will produce more NOx because oil burns hotter than natural gas.
Reason for emission control: NOx is a leading cause of air pollution in big cities with large volumes of vehicular traffic. It works as an oxidation medium and reacts with volatile organic compounds (VOCs) to create smog, which affects the ozone layer, especially when temperatures are hot. NOx also contributes to the creation of acid rain.
Carbon Dioxide (CO2): Carbon dioxide is a gas that consists of one part carbon and two parts oxygen. It is created by humans
Reason for emission control: CO2 is among the causes of climate change and plays a part in respiratory diseases from air pollution.
Particulate Matter: Particulate matter (or atmospheric aerosol particles) is a collective term for the microscopic liquids and solids in the air that are hazardous to health. These include soot, pollen, dust, and smoke.
Reason for emission control: Particulate matter holds droplets and solids so minuscule (10 micrometers and less) that they are inhalable and can create health issues. Particles under 2.5 micrometers, called fine particles, are the most destructive to health and cause haze across America.
Environmental laws across the United States require gas boilers to have an annual efficiency of at least 90 percent to be considered ENERGY STAR certified. US boilers are required to be rated using a measurement called annual fuel utilization efficiency (or AFUE). This assesses and tallies beneficial heat that is pumped into your home in comparison with the measure of fuel that is depleted.
New or modified high-efficiency boilers are 90-99 percent efficient, while old pilot-light boilers have a much lower efficiency rate of between 56 and 70 percent.
Your boiler will benefit from having a thorough cleaning to not only ensure the efficiency of the unit but to guarantee your boiler passes the annual emissions test required to keep it running.
If your boiler is older, you may even choose to have it retrofitted or replaced by a higher efficiency model. Have a heating contractor come to your home to assess the size of the boiler required to keep your home warm- with modern improvements made to boilers, you may find that you can use a smaller boiler to sufficiently and efficiently heat your building.
Call Ragno Boiler Maintenance for all of your boiler service needs.