HVAC stands for Heating, Ventilation and Air Conditioning. This system controls heating and cooling in an interior space. It includes heat pumps, furnaces, ductwork, air conditioners, thermostats, and certain controls. Air conditioning, on the other hand, is the process of maintaining indoor temperatures, relative humidity, and air purity. ACs are used in closed interior spaces to attain a cooling comfort in summer.
How do AC and HVAC systems work?
The working of an HVAC system
Talking about HVAC, there are many moving parts in it. However, to understand the functioning of an HVAC system, you first need to understand the functioning of its various parts. Let’s try to learn more about HVAC by studying its anatomy and physiology.
Thermostat: Thermostat is a visible component of an HVAC system. It is usually mounted on a wall and can be programmed to maintain an ideal temperature in your home. The thermostat activates your HVAC system to circulate air whenever the temperature in the room gets uncomfortably high or low.
Furnace: Furnace is the heart of your HVAC system. It is usually large and takes up more space compared to other components of the system. The furnace heats up air and then distributes it through ductwork or pipes to other areas of the home. A furnace can use a variety of heat sources such as heat pumps, solar energy, electric resistance and combustion.
Evaporator coil: When your thermostat is set at a lower temperature, the evaporator cools down the air. The cold air is then blown throughout your home.
Condensing unit: This unit remains located outside your home and is filled with a refrigerant gas. The condensing unit cools the refrigerant and pumps it to the evaporator coil, where it is transformed back into gas.
Vents: These outlets distribute heated and cooled air through the duct system to your entire property. These vents are located near the ceiling and have angle slats that allow the air to flow downward. Your HVAC system ceases to operate properly when vents get blocked.
Refrigerant lines: These lines are used for carrying refrigerant in the form of gas to the condensing unit. Here, it gets covered into liquid, which is then carried back to the evaporator coil.
All the above mentioned parts work in coordination; and that is essentially how HVAC systems work.
The working of ACs
Usually central heating and cooling systems provide cool air by using ductwork within your home. The process draws in warm air from the inside and throws it outside.
In a split system, there are two units— an internal and an external unit. The external unit comprises the compressor and the condenser. The compressor forces hot, high- pressure gas into the condenser where it converts into a cool liquid. This liquid travels to the indoor evaporator coil or cooling compartment. The fan in the indoor unit circulates the air inside to allow it to flow across the fins of the evaporator. Here, heat exchange takes place between the refrigerant and the surrounding air. In the process, the cool refrigerant in the evaporator gets back into its hot gaseous form, while cooling down the air in its surrounding. It is this air that cools down your home.
The gas in the evaporator travels back to the outdoor unit where it again gets converted into a cool liquid by releasing all of its heat. It’s now ready to start its journey all over again. This continues until your home cools to the desired temperature, according to your thermostat settings.
How are AC and HVAC systems similar?
Although the two acronyms differ, they are all the same and often interchangeably used by common people as well as professionals in the air conditioning industry. AC generally refers to the air conditioning unit, designed to cool the air and control the humidity of the room. While the HVAC system performs both the functions; heating and cooling. Hence AC units can be considered as a part of the HVAC system. Additionally, the HVAC system also performs ventilation and provides fresh air. While AC and HVAC are the same thing, the types in which they are found may vary widely. There are numerous types of heating or cooling products available on the market.
What sets the two apart is the fact that ACs are not used for heating the air. Except some which are capable of heating your home. Air conditioning is a cooling mechanism. An air conditioner can be a small box that fits in a window, or it can be a large unit that cools your entire property. You will need an HVAC system if you live in a cold climate where it is necessary to keep warm in winters. An AC simply won’t be able to generate such extreme heat as the HVAC system does.
Talking about air quality, a lot of ACs do promise to purify air, but HVAC systems provide complete air quality control. Hence, HVAC systems are the best option for indoor air quality issues. Both the air conditioner systems should be installed by professionals. If you are living in San Diego, where winters are long and cool, summers are short and warm, you should go for an HVAC system to feel warm in winters and cool in summers. Need hvac installation San Diego, you just need to google it, and you will get the best players out there.
Longevity of AC and HVAC systems-
This depends on the amount of time for which your equipment is used, its exposure to corrosive chemicals, the current condition of the equipment, the quality of maintenance, the extent of major repairs they have gone through as well as the reputation of the brand from which you have bought your unit. These variables can considerably impact the life expectancy of both AC and HVAC systems. An average HVAC system lasts about 20 years. Modern air conditioners too are capable of lasting between 15 and 20 years. The older models, however, have a shorter life span and offer about 10-12 years of service.