What Is An HVAC System?

What Is An HVAC System? – The initials HVAC stand for Heating, Ventilation and Air Conditioning. They describe the functions of an HVAC system. This mechanical system’s design is primarily an attempt to take control of the environmental conditions inside the space you work.

The main functions of an HVAC system

An HVAC system is designed to control the environment in which it works.

It achieves this by controlling the temperature of a room through heating and cooling. It also controls the humidity level in that environment by controlling the movement and distribution of air inside the room.

The system also ensures cleanliness of air inside the said environment.

Types of HVAC Systems Available

The three main types of HVAC systems available today are:

  1. Split and Window AC
  2. Packaged Heating & Air Conditioning System
  3. Central AC System

How Does the System Work?

Not all types of HVAC systems work the same way. Some are faster than others while others serve larger environments. In short, some HVAC systems are more effective than others in certain situations.

Here’s how the different systems work:

  • Split and Window AC Systems

In a window AC, fans blow air through the coils. This improves how they separate the heat and cold. Heat gets lost to the outside air while introducing cold is into the room.

Split ACs are used in larger application areas than window ACs. The split AC focuses on splitting the cold from the hot side of the system. The cold side has the cold coil and the expansion valve. This is usually placed inside a furnace or any other form of air handler. The handler blows air over the coil and the cooled air is distributed to various rooms in the building through the air ducts.

  • Packaged Heating & Air Conditioning System

These units provide an all-in-one benefit in that they have both heating and cooling equipment in a single “package”. Users can place them in mechanical rooms, on the rooftop or at a grade close to the conditioning space.

Unlike in split systems where the cold and hot units are separate, the package AC has all the components in one unit. These elements have a centrifugal fan or blower that helps distribute the air throughout the elements of the structure.

  • Central AC Systems

Most of the air conditioners in residential buildings are in the form of split systems – only bigger. They have a cooling fan, a condenser coil and a compressor housed in a separate condensing unit. The evaporator coil is usually inside an air handler (indoor) unit normally installed on the furnace. When the furnace is electric, a blower is included in the system.

The compressor uses electricity as its source of power to pump the refrigerant across the system collecting indoor heat and removing it from the home. The heat dissipates outdoors by the coil in the condensing unit.

Warm air indoors gets blown through the indoor coil (cold) to remove moisture and heat. The heat in the air transfers to the coil and thus the air cools. The water vapor condenses on the coil (since it is cold) and collects inside a drain pan. It goes outside through the condensate drain.

The heat, after flowing to the evaporator coil, pumps outdoors while the now cooled air inside the room circulates through the fan on the air handler. Hence, the indoor temperature is maintained.

How Much Energy Does the System Use?

There are several determining factors to the quantity of energy that a system uses. They include:

  • The efficiency of its components
  • How appropriate its size is in relation to your home
  • Your local climate
  • How much you use it
  • The type of fuel it uses

When evaluating the system’s expected consumption of energy, you need to follow industry-standard rating systems. Some of them are:

  • The SEER (Seasonal Energy Efficiency Ratio)

This measures a heat pump system or air conditioner’s cooling efficiency. The higher the SEER the greater the efficiency and the energy saving capacity; Federal law requires new cooling systems to have a minimum rating of 13 SEER.

  • The AFUE (Annual Fuel Utilization Efficiency)

This rates oil or gas furnaces to show the amount of fuel used in heating your home and the wasted amount. The rating is in percentages and the higher the AFUE rating, the more energy-efficient the system is. It is a requirement by law United States-manufactured furnaces should have a minimum of 80% AFUE.

  • The HSPF (Heating Seasonal Performance Factor)

This one measures the level of efficiency of a heat pump’s heating mode. A high rating means greater efficiency and savings on cost. The law requires new heat pumps to have at least a 7.7 HSPF.

  • The Wattage

Wattage rates the amount of electricity your ventilation, air conditioning and heating system uses to provide a comfortable environment for you and your family. The unit of measurement is kilowatt-hours. Speed is the main determinant of the wattage of your system.

It is very important to take into account the efficiency and energy usage of a system before deciding to buy it. These two factors will go a long way in helping you determine the cost-benefit ratio and whether it’s worth it.

How to Select the Right HVAC System for Your Needs

When looking to buy an HVAC system, it is important to consider certain factors to ensure you select the most appropriate one. These factors include:

  1. The age and size of your home.
  2. The number of rooms you want to air-condition.
  3. Local climate.
  4. Utility costs at the local and regional level.
  5. The available warranties.
  6. The type of system that meets your custom needs best.

An HVAC system ensures maintenance of your home temperature and humidity in an economic way that is not only effective but also takes care of the environment. If you think your home or workplace needs air-conditioning, consult a HVAC engineer to determine the system that’s best for your situation. Also, make sure you work with only qualified personnel when buying and installing the system.

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