A fully functioning HVAC system is crucial for a healthy and comfortable home. The main unit of an HVAC system includes the air conditioner, heat pump, or oven. These are the parts where the heating and cooling of your home takes place. However, they do so with the help of other internal and external mechanics.
Modern homes rely on HVAC systems to maintain indoor air quality and comfort during season changes. However, what exactly is HVAC? The acronym stands for “heating, ventilation and air conditioning. Understanding more about these three components of the HVAC system can help you enjoy a healthier and more comfortable living environment. As the brain behind a domestic HVAC system, the thermostat deserves the first mention.
Basically it is a thermometer with a direct connection to the heating and cooling components, allowing you to control when the oven and air conditioner turn on. Today, there are many types of thermostats available, including programmable models that automatically change the temperature according to the program set by you. You may also decide to install several thermostats for zoning purposes. The oven and blower motor are two main parts of a home HVAC system.
The oven is quite large and usually requires its own space in the basement, attic or closet. Each oven has a heat exchanger, which starts when the thermostat asks for heat. If the oven runs on gas or oil, the burners perform the heating. If the fuel source is electricity, electric coils heat the air.
It is important that the heat exchanger remains sealed, as furnaces using natural gas or petroleum fill the heat exchanger with combustion fumes, including poisonous carbon monoxide (CO). Under normal conditions, a vent sends cooled fumes to the outside, where they are harmlessly dispersed into the air. However, if the heat exchanger is cracked, these fumes could enter your home, potentially endangering you and your family. That's why preventive maintenance is so important.
When you imagine the parts of a domestic HVAC system responsible for cooling, this is the component that normally occurs to you. It is the metal unit that is located outside the house and is responsible for expelling the heat absorbed from the indoor air to the outside. This prepares the refrigerant for another round through the evaporator coil, where it absorbs more heat and cools your home even more. Without refrigerant, air conditioning wouldn't be possible.
The refrigerant lines are comprised of copper or aluminum and run between the indoor evaporator coil and the outdoor condensing unit. Hidden inside the air controller of your central air conditioner, the evaporator coil plays a leading role in keeping your home cool and comfortable. Lined with thin aluminum fins, the evaporator coil looks and functions almost like a car radiator, except that it absorbs heat rather than rejects it. As cold refrigerant enters the evaporator coil, it also draws latent heat from the air passing through the coil.
Capturing this thermal energy transforms coolant from a cold mist to a hot vapor. Meanwhile, the air passing through the evaporator coil loses its heat and moisture, resulting in fresh, dry air being fed throughout the house through the ducts. Evaporator coils are mainly protected from dust and dirt thanks to the HVAC air filter. However, an evaporator coil generally needs annual cleaning to prevent dust and debris buildup from affecting its performance.
Given how easy it is to damage the evaporator coil, it is important that you hire a professional to perform this cleaning for you. The compressor is at the heart of the central air conditioner. Without it, keeping your home cool and comfortable would be an impossible task. You can find the compressor for your central air conditioner in the outdoor cabinet next to the condenser coil.
As the name implies, the compressor absorbs hot refrigerant vapor and compresses it into a denser form. This process also causes an increase in temperature and pressure, causing the coolant to be hotter than before. The pressurized refrigerant is finally pushed through the condenser coil. Like the evaporator coil, the condenser coil also plays an important role in the operation of the central air conditioner.
However, unlike the evaporator coil, the function of the condenser coil is to release heat from the refrigerant. Think about your car's radiator and how it's designed to help dissipate heat from the coolant circulating inside it. In fact, the way the condenser coil works is quite similar to how the evaporator coil works. A condenser fan integrated in the outdoor cabinet directs ambient air through the condenser coil in a manner similar to how the built-in fan of the indoor air controller directs air through the condenser coil.
But instead of absorbing latent heat, the condenser coil uses airflow to expel heat from the refrigerant. There's not much your central air conditioner can do with refrigerant that is in liquid form. In its current form, it will not be able to absorb latent heat as it circulates through the evaporator coil. To complete the air conditioning process, the refrigerant must be transformed back into a cold mist.
This is where the expansion valve comes into play. The expansion valve essentially converts the liquid refrigerant flow back into vapor form. Liquid refrigerant enters the valve through an extremely narrow orifice designed to measure the amount of refrigerant passing through it. A temperature-sensing bulb helps modulate coolant flow based on temperatures inside the suction line.
As liquid coolant passes through the orifice, the coolant undergoes a significant reduction in pressure. The resulting pressure drop also causes the coolant to expand in the form of a mist. The rapid expansion also throws out a large amount of thermal energy, rapidly cooling the coolant in the process. The end result is the refrigerant that returns to its cold mist form in preparation for its journey through the evaporator coil.
As you can probably guess, that part is the compressor. It is true that the compressor is the “heart” of HVAC and is the one that works the most. However, we caution you to remember that many system problems do not originate with the compressor. When you experience premature compressor failure, it often means that there is another problem that has gone unnoticed.
Air conditioning in a commercial HVAC system is very similar to a residential unit. Its purpose is to dehumidify the air and remove heat. It is important to remember that the air conditioner itself does not cool the building, but works with many other subsystems to regulate the temperature. The condenser is the heat exchanger that serves as the hot side of the air conditioning unit.
It removes heat from the building and transfers it to the outside. Gaseous refrigerant becomes liquid refrigerant. A heat pump can also have a condenser, in which case it functions to collect heat from the outside. The expansion valve is an essential part of the condenser's function.
Eliminates liquid coolant pressure so expansion can occur, converting liquid substance to vapor. Expansion valve provides precise control of refrigerant flow in the evaporator coil. Of all the different parts of the air handler, the evaporator coil is the one most likely to need maintenance or replacement. The evaporator coil contains the cooled refrigerant received from the compressor.
As the air from the blower fan moves over the coil, heat is removed from the air in the treated area. Chillers come in air- and water-cooled varieties. Its function is to remove heat from the liquid passing through the pipes of the structure. In an air-cooled chiller, the condenser coils are cooled with fan-driven air, and the unit is usually located outdoors.
HVAC systems are milestones in building mechanical systems that provide thermal comfort to occupants, along with indoor air quality. HVAC systems can be classified into central and local systems according to multiple zones, location and distribution. Main HVAC equipment includes heating equipment, ventilation equipment, and refrigeration or air conditioning equipment. Central HVAC systems are located away from buildings in a central equipment room and supply air conditioning through a supply duct system.
Central HVAC systems contain all-air, air-to-water and water systems. Two systems should be considered central, such as heating and cooling panels and water source heat pumps. Local HVAC systems can be located within or adjacent to a conditioned area and no ducting is required. Local systems include local heating, local air conditioning, local ventilation, and split systems.
The design of equipment rooms to house both pieces of equipment should consider the size and weight of the equipment, the installation and maintenance of the equipment, and the regulations applicable to the combustion air and ventilation air criteria. This type of system is considered a local HVAC system, since each equipment serves its area without crossing the boundaries to other adjacent areas (e). The distribution system mainly varies according to the type of coolant and the method of delivery, such as air treatment equipment, fan coils, air ducts, and water pipes. The main disadvantage is the lack of air ventilation, similar to total water systems as in fan coil units.
Some of the most important parts of your HVAC system are the heat exchanger, fan motor, combustion chamber, condenser, evaporator and thermostat. The piping system is used to deliver coolant, hot water, chilled water, steam, gas and condensate to and from HVAC equipment in a direct, quiet and affordable manner. In the case of reusable gowns, final products are biodegradable when cotton or biodegradable polyester fibers such as polylactic acid (PLA) are the main components. The key to keeping the system up and running is regular maintenance, taking into account all components and operating environment.
It is preferable to be located in the center of the building to reduce the long stretches and sizes of conduits, pipes and conduits, to simplify well design and centralize maintenance and operation. Among the different parts of your HVAC system, a thermostat is one of the most visible inside the house. The main disadvantage is that the controlled air flow rate can adversely affect other adjacent areas with a different or similar air flow and temperature. To save energy and avoid problems with your HVAC system, you should keep fallen leaves, grass clippings, dirt, and other debris away from the condenser.
You can find HVAC systems anywhere, from single-family homes to submarines, where they provide the means for environmental comfort. The fan in your HVAC system blows warm air from your home through the return ducts and over the evaporator to cool it, and then distributes the cool air through the ducts and into the rooms of your home. . .
