What is an HVAC System?
If you didn’t know, the term HVAC stands for heating, ventilation, and air conditioning and concerns the technology of indoor and vehicular environmental comfort. It’s composed of different systems that are used for moving air between areas. HVAC system design is a sub-discipline of mechanical engineering, based on the principles of thermodynamics, heat transfer, and fluid mechanics.
HVAC is an integral part of society's modern residential structures. You can find them in family homes, apartments, hotels, senior living facilities, medium to large industrial and office buildings. You might not know this, but such systems are also used in ships and submarines.
What’s the Difference between HVAC and an AC?
You may well have heard the terms HVAC and AC used interchangeably, which is not right (to an extent). HVAC refers to a system meant for heating, ventilation and air conditioning, while the term AC simply refers to air conditioning.
AC provides cool and fresh air for a room/area. Window units and central AC are the widely used standard systems. However, HVAC can include heat pumps, gas furnaces along with air conditioning units. This means that the HVAC encompasses both heating and cooling and also covers ventilation and duct work.
Benefits of HVAC
Some of the advantages of installing an HVAC system are:
- Reduced energy costs
A traditional heating and cooling system consumes almost half of the energy that the house uses. A number of studies have indicated that these energy-efficient systems can help decrease your bills by at least 20 percent. Moreover, installing a smart HVAC system lowers your carbon footprint and is an excellent step towards maintaining an environmentally friendly space.
- Temperature variability
An HVAC system offers users the ability to control the temperature inside their home. With this kind of set up, you can heat or cool specific areas of your house as you desire.
- Cleaner air
HVAC systems can detect elevated carbon dioxide levels that are harmful to the human body. When this happens, the system increases the amount of fresh air, thus reducing stuffiness or any potential harmful gases.
- Remote access
A Smart HVAC system means you can remotely control the temperature in your house or apartment. With a few taps on your device, you can start heating or cooling your house before you arrive. If you like the idea of a warm (or cool) welcome, having such a set up is the way to go.
What is included in an HVAC system?
As indicated by its name, an HVAC system includes 3 systems, as follows:
1. Heating
Heaters are installed to warm the building. This can be done through central heating and contains a boiler or a furnace to make the air hotter. The heat can be transferred by conduction, convection, or radiation.
2. Ventilation
Ventilation is the process of adequately replacing air in the space, controlling the levels of odors, airborne bacteria, oxygen, carbon dioxide and temperature. It’s one of the crucial features for maintaining the appropriate air quality in the room and has 2 forms:
- Natural ventilation: The ventilation of a building with outside air without using fans or other mechanical systems. This can be done with operable windows, louvers or trickle vents when spaces are small and the architecture permits it.
- Forced/mechanical ventilation: Mechanical or forced ventilation is provided by an air handler (AHU) and used to control indoor air quality. The problems of excess humidity, contaminants and odor can often be solved through dilution or replacement with outside air.
3. Air conditioning system
An air conditioning system works to provide cooling and humidity control for all or part of a building. It’s achieved by removal of heat through radiation, convection or conduction. The heat transfer medium is a refrigerant system.
How does HVAC work?
First, there needs to be an efficient source of fresh air intake which can be from the outside or from within the home. This process is called ventilation (as above, it’s either natural or forced ventilation). Once the air is brought in, it’s drawn into an air handling unit where the actual work occurs. Here, the air is purified from dirt, dust and other particles.
Next is the comfort factor. Air is sent to be heated or cooled and to remove excess humidity. Once the air is considered to be clean, fresh and at a preferred temperature, it’s directed into the home or workspace through ducts or directly into the (targeted) space.
What are the Different Types of HVAC units?
When installing an HVAC system, you should know what type of HVAC system is suitable for the area. Here are some of the varieties which can help you with your decision:
- Heating and cooling system: These tend to be the most common types of HVAC systems and is split between 2 main units. One unit is meant for heating and the other for cooling. These systems are easy to notice because they contain both indoor and outdoor units. These types of HVAC units feature an outdoor cooling system which uses refrigerants, compressors and coils to cool air. It also has a heater (usually located in a basement or other storage space) which uses gas to warm the house. This system uses a traditional thermostat to manage the temperature.
- Hybrid split system: These HVACs are similar to the split systems but with some key differences. A hybrid has the ability to switch between gas power – which is quicker and more complete – to electric, which is more efficient and quieter. In addition to all the benefits you would expect from a split system, the hybrid utilizes traditional ducts as well as thermostats. This split system, when on its electric setting, also helps you to conserve energy and lessen utility bills.
- Duct free (Mini-Split): This unique system may have significant upfront costs the but big benefits offset the initial expense. These are individual HVAC units set up separately for each room of a building. They offer greater independent control making it suitable for businesses like hotels and venues. These units are mounted on an indoor wall and typically connected to an outdoor compressor. Another advantage is that prevents energy wastage of unused rooms thanks to the independent controls. However, with so many potentially in just a single building, duct-free systems require regular and intensive cleaning and maintenance.
- Packaged heating and air: This system is a contained heating and air unit that happens to be stored inside the house. You will usually see them installed in an attic or top floor storage space. This type of HVAC is use to both cool and heat a building and due to its compact size is a good match for smaller homes. These types of systems are both efficient and very easy to maintain. Bear in mind that they aren't as powerful as larger options and are recommended for areas don’t need to be overheated. The heat is generally electrically generated but other forms that can combine gas and electric are also available.
Every type works best for a specific place or environment. The split system happens to be the most generally used while hybrid models are on the rise due to the system's energy-efficient build. Mini-split systems are perfect for the service industry and packaged heating is perfect for small places or warm climates.
Common HVAC Ratings and Certifications
When looking for a new energy-efficient HVAC system, you'll spot a variety of energy efficiency ratings on the units. To ensure you're getting the best HVAC system, it's worth knowing who is rating them, how they are ranked and which are fairing better.
- AHRI: The Air Conditioning, Heating, and Refrigeration Institute works as an independent lab that is tasked with certifying whether or not a manufacturer's efficiency claims about a system are true.
- AFUE – Annual Fuel Utilization Efficiency. It involves measuring the efficiency of a gas furnace that is used for converting fuel to energy.
- EER – Energy Efficiency Ratio. It measures how efficiently a cooling system operates when the outdoor temperature reaches a specific level.
- SEER – Seasonal Energy Efficiency Ratio determines air conditioning efficiency and heat pump cooling.
- HSPF – Heat Seasonal Performance Factor measures the heating efficiency of heat pumps.
- MERV Rating – Minimum Efficiency Reporting Value is a standard used to rate the overall efficiency of air filters.
HVAC Maintaining Tips
Regular maintenance means prolonged life of a product. Since an HVAC system is expensive to install, ongoing ‘health checks’ are essential.
Top maintenance tips:
- For a system that heats and cools, perform a maintenance check in the spring and fall.
- For cooling system maintenance only, perform maintenance at least once a year, ideally before the warmer temperatures/seasons.
- For furnace maintenance only, undertake a check at least once a year, before the colder months when you require more heating.
When is it the right time to replace your HVAC system?
An old or damaged HVAC system can lead to a variety of issues for homeowners. You don't want increased energy bills and poor indoor air quality, right? If you’re not sure whether it's time to invest in a new HVAC system, here are a couple of indicators to help you know when it's time to replace your HVAC system.
- When repairs the cost more than half of the expense of a brand new AC
- Energy bills keep on increasing
- When you can’t keep your home at a preferred temperature
- You notice more dust in your house
- Wiring that is melting away or mold in the ducts can produce unusual smells
- When you start hearing noises such as grinding and squealing
- When you have poor air quality.
If you’re still unsure and wondering whether it is time to replace your HVAC system, you should call a technician to carry out an inspection.
What does a technician do?
Most people assume that HVAC technicians just fix AC units and heaters. However, other aspects of the profession are not so obvious. For example, they also specialize in HVAC micro-niches such as water-based heating and commercial refrigeration.
Primary Duties of a Technician:
- Looking for problems and malfunctions in the system
- Installations and repairs
- Advising product manufacturing teams regarding needed equipment
- Installation of system wiring
- Providing regular maintenance of the system (Cleaning ducts, checking fluid levels and installing new filters).
Drawbacks of an HVAC system
We wouldn't be comfortable creating a complete guide for HVAC without listing some of the possible drawbacks.
- Leakage problem: The HVAC system can break when there is a lack if regular upkeep, causing leakage problems in the boiler heater, and circulation pumps.
- Expense: An HVAC system can be costly to install, repair, maintain and replace
- Lack of qualified technicians: A professional, reliable technician can be hard to find. That's why it’s recommended that you reach out to Bird Fuels for a trusted and recommended source, instead of wasting money.
The Bottom Line
Cooling and heating systems are a big part of energy expenses, make sure that a smart and effective HVAC system is used. This will help to keep down expenses and prevent problems arising.
Consider this. The average life of an HVAC system is 20 to 25 years, so make sure regular maintenance is done to extend its life. You want to get the most out of your investment, right?
If you’re in the market for HVAC, allow Bird Fuels to help you out. We offer residential HVAC sales, service, and installation. Our professional team of HVAC technicians is ready to lend a hand to ensure your home is as comfortable as you like.