User:Heating Processes and Units

Heating Processes and Units include burners, boilers, air conditioners, hot water heaters, and furnaces. All of these devices add to the process of heating (or cooling) the home. Below are definitions of the separate components listed.

Oil Burners: An oil burner is a heating device which burns fuel oil. The oil is atomized in to a fine spray usually by forcing it under pressure through a nozzle. This spray is usually ignited by an electric spark with the air being forced through by an electric fan.

Variety of burners: Riello, Beckett, Carlin

Boilers: A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.

Variety of Boilers: Peerless, Weil-McLain, Williamson, Dunkirk, Crown, Pennco

Air Conditioners: An air conditioner (often referred to as AC) is a home appliance, system or mechanism designed to dehumidify and extract heat from an area. The cooling is done using a simple refrigeration cycle. In construction, a complete system of heating, ventilation and air conditioning is referred to as "HVAC". Its purpose, in a building or an automobile, is to provide comfort during either hot or cold weather.

Variety of Air Conditioners: Armstrong, Goodman, Ruud, Rheem

Hot Water Heaters: Heats and maintains the temperature of water for homes and businesses.

Variety of Hot Water Heaters: Bock, Aero, Bradfordwhite, State, Williamson, Crown, Tempstar

Furnaces: A furnace is a device used for heating. The name derives from Latin fornax, oven. The earliest furnace was excavated at Balakot, a site of the Indus Valley Civilization, dating back to its mature phase (c. 2500-1900 BC). The furnace was most likely used for the manufacturing of ceramic objects.

Variety of Furnaces: Miller, Armstrong, Tempstar

Each of these devices has its own purpose and efficiency that varies depending upon the size, brand, and quality of product along with the installation and of course the area of the space being heated or cooled.

How A Boiler Works

Add and Ignite Fuel

A boiler has a separate container attached to it called a burner. The fuel that is used to power the boiler and create the steam needed to heat a home is burned or released into the boiler from the burner. The types of fuel used in household burners are either natural gas, wood chips or oil. Natural gas is supplied through a specialized pipe and released into the boiler, oil is sent through a pressurized tank, while wood chips are blown into the burner. These fuel sources mix with the air and are ignited to create the heat necessary to boil water and create steam.

Water Heats and Steam is Made

Once fuel has been added to the burner and heated to a desired level, the combustion gases that a particular fuel type produces or the fire from the fuel is released into the boiler in order to heat the water inside. Depending on the type of boiler, this can happen in one of two ways--in firetube boilers where fire or gas is sent through tubes that run into the boiler and are surrounded by water and watertube boilers work that in the opposite way--where water runs through a series of pipes and fuel combustions are sent into the boiler to surround them and heat the water. These are rarer, but they are essential when large amounts of steam and heat are necessary. As the water heats, temperatures raise to over 212 degrees Fahrenheit, which is when steam is produced. This steam is the key to providing homes with warmth.

Heat Travels throughout the Home

Once steam has been created by the combination of fuel and water, it is then channeled throughout the home. This happens via radiators, under floor vents and specialized pipes that run throughout a home. Some steam is kept contained within the boiler as it works, since the amount that travels from it needs to be contained. Otherwise, the home will become overheated. Since steam builds up more as temperatures rise, it's important to keep track of the boiler while it's running in order to make sure that the steam inside does not build up too much pressure. It's because of this that boilers cannot run continuously, even during the winter months. They must be turned off and on at various intervals in order to not only keep a home warm, but also safe.

How The Burner Works and Allows The Boiler To Do Its Job

Heating oil in liquid form must be turned into vapor and mixed with air before it can burn. The oil pump lifts the oil from the storage tank, pressurizes it and delivers it to the burner's nozzle that sprays the oil in a fine mist of small droplets. This process is call atomizing. These droplets are mixed with air and then ignited by a spark from the burner's ignition system.

The flame from the oil burner heats the air in a heat exchanger inside the boiler or furnace. On one side of the metal is the flame, and on the other is the water or air that circulates in the house. All of the emissions from the oil flame (mostly nitrogen, water, and carbon dioxide) are sent up the chimney.

How An Air Conditioner Works

Air conditioning units work on basically the same principle as kitchen refrigerators, only without the box. Contrary to popular perception, air conditioning is not about adding cool air to the room, but more about drawing heat away from it. The end result is a space with significantly less heat, which makes it feel cooler to occupants. Air conditioning takes advantage of the effects of evaporation, much like a swab of alcohol makes a person's skin feel cooler as the liquid evaporates. The alcohol doesn't lower the person's skin temperature, but rather draws away heat from the air as it turns to a gas.

Air conditioning units contain a special chemical called a refrigerant, which has the unique ability to change from a gas to a liquid in a short amount of time. A refrigerant called freon is commonly used in air conditioning units, although there are other commercial refrigerants available. The refrigerant is pumped into the air conditioning unit at the factory, along with a small amount of lubricating oil for the compressor, an essential part of the air conditioning process.

The parts of a typical air conditioning unit usually form a closed system consisting of a compressor, a condenser, an expansion valve and a thermostat. Motorized fans help to circulate the conditioned air, while thin metal fins allow heat to dissipate quickly. The heaviest part of a typical air conditioning is often the compressor, since it must be strong enough to withstand a significant amount of pressure.

Air conditioning begins with the refrigerant entering the compressor, usually located at the bottom of the unit. At this point, the refrigerant is a cool gas. As the gas enters the compressor's inner chamber, the compressor squeezes the refrigerant and the gas becomes a very hot gas under high pressure. This hot gas goes through a series of condensing coils placed outside of the room being cooled. The heat dissipates into the outside air, much like a car's radiator dissipates heat from the engine coolant. Once the refrigerant reaches the end of these coils, it is significantly cooler and in liquid form.

This liquid is still under high pressure, like the contents of an aerosol can. In the case of air conditioning, the liquid refrigerant is forced through a very tiny opening called an expansion valve. The liquid refrigerant comes out of the other end of the expansion a very small amount at a time. Because the refrigerant evaporates at a much lower temperature than water, it begins to evaporate while traveling through another set of coils. It is this evaporation action that draws heat out of the surrounding air, including the air contained in the room. The air conditioning unit's fan blows across metal fins placed over these coils, causing the sensation of cooling in the room.

At this point, the liquid refrigerant has become a cold gas again and re-enters the compressor, where the entire process begins again until a thermostat registers a specific temperature and shuts off the compressor. When the room warms up, the thermostat senses the added heat and the compressor kicks back on to create more of the hot pressurized gas. At some point, the temperature of the room may equal the cooling power of the air conditioner and the compressor will shut off again. The air conditioning systems of most houses do benefit from energy-saving steps such as using window shades and keeping doors closed, since they don't have to work as hard to keep the room at an acceptable level of cool.

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