When we enter a room or a building, what we usually notice is the smooth airflow, which makes the atmosphere comfortable. It is a fusion of air efficiency, regulating workflow and selecting the right equipment. However, the centre of this complicated mechanism is the HVAC system. In one way, it takes care of the heavy lifting of air circulation; in another way, it makes the space livable. The challenge of building a suitable HVAC system starts when you choose the wrong fan type.
In this article, we explore the different types of HVAC fans in the market and their distinguishing characteristics.
The Function of HVAC Fans
- The main function of the HVAC fans is to carry airflow through the various heating, ventilation and cooling systems to a particular destination. Fans are the main element that brings conditioned air to a certain space and help make air circulate within every corner of the building.
- The mechanism is not that complex to understand. First, the HVAC fans haul air using filters, then bring air through the ductwork, targeting higher quality airflow within the room or building. The prime focus of this mechanism is to keep a coherent temperature level within the space. There will be no functioning of the HVAC system without the fans. Fans are the main component that contributes to regulating air transmission, increasing efficiency and comfort.
- Making the passage for hot or cold air is not the only functionality of HVAC fans, as going beyond that, they also simply supply a consistent airflow and level up the air quality inside the space. When an HVAC system is installed, there will be no hot or cold spots in a building, as it modulates everything as per the pre-defined guidelines.
4 Types of HVAC Fans
Centrifugal Fans
Centrifugal fans are also referred to as radial fans, and we can see this type of fan in the central air conditioning and heating networks. The speciality of them is that they carry a central board alongside a network of blades spinning in a rounded pattern. The system drags air through these whirling blades, then pushes it out back.
Even though there are various obstacles, such as ducting and filters inside the system, this has the power to make a massive load of air move efficiently. This workflow supports central air conditioning and heating systems that regulate a consistent quantity of airflow to all the corners of the building.
Not limited to commercial air handling systems and industrial ventilation, centrifugal fans are used in several industrial scenarios, as their application can be quite flexible and versatile. One of the most outstanding qualities of the said fans is their adaptability and endurance. This indicates that centrifugal fans can cater to a diverse range of industrial requirements, adjusting highly and bearing a higher static pressure while governing airflow.
Axial Fans
We mentioned in the above section that centrifugal fans twist their blades in a circulation motion within the system. When it comes to the axial fans, they keep rotating airflow in a parallel manner. This way, the axial motion produces a more efficient and straightforward blow. The latter is undoubtedly an excellent choice when you expect to drag a whole load of air with a little resistance for regulating purposes.
We can see these types of HVAC fans mainly in the air-cooled chillers, condenser units, and cooling towers. Axial is the number one design choice in the industry when they need to control a constant, one-way flow of air to reduce heat in a building.
Since the axial fans consume lower levels of energy, this is a sustainable choice as well as a cost-effective option.
Mixed Flow Fans
Mixed flow fans are a combination of the characteristics dragged down from the above-mentioned fan types: centrifugal and axial. It comes with the capacity to endure high pressure and move a massive load of air through its system, and offers the best benefits of radial and axial fans’ blow patterns. Another unique feature of the latter is that it has angled impellers to boost efficiency and adaptability to significant levels.
Adaptability is the main reason many HVAC networks employ mixed flow fans within their mechanisms. Its application is quite varied, from cooling, ventilation and air handling units, etc. If the expectation is to regulate a large volume as well as the airflow, then industry experts tend to select mixed flow fans.
It offers a versatile hybrid air circulating mechanism adjusting to diversified system requirements, which makes it stand out as the best choice of HVAC professionals.
Crossflow Fans
The crossflow fans are also known as tangential fans, come with a distinctive design and blade functionality. For example, it is bundled with the ability to include an impeller that thrusts air in a vertical direction into the intake. Since the design of the fan is compact, these are suitable for places with limited space capacity. Also, this type of HVAC fan is highly efficient.
It is capable of covering each corner of the room or a much larger area with its uniform blow, and this is popular as one of the significant features of crossflow fans. When the system requires a steady airflow distribution in cases like unit heaters, convectors, and small air handling systems, the latter is the ideal solution.
Main Considerations When Selecting HVAC Fans
No matter what fan is concerned for a HVAC system, it must take forced ventilation into consideration as the main factor, to ensure the constant movement of air under pressure. The other key factors are:
Fan Type
When selecting the HVAC fan, one of the main points is undoubtedly what type of fan we need to opt for. It is true that this is used to bring the airflow from one particular place to another while regulating it, yet the expectation from each fan can be different. Depending on the airflow type, the space of the area, and airflow pressure, the professionals decide which fan would offer the best outcome.
Airflow
All the HVAC fans come with a CRM airflow. When it is clear as to which type of fan is suitable, the HVAC operators then determine the required airflow.
This is the formula for calculating CFM.
Room Volume = LxWxH CFM = Room Volume ÷ Min/Variation
Noise Level
No matter what mechanical element we talk about, noise is another fact we cannot avoid. This is where the HVAC experts consider the noise level the fan produces when in action. Imagine this is used in a peaceful apartment area or a school, and what would happen if the HVAC fans keep functioning with an unbearable noise level? The area space, the type of building, and everything need to be considered when choosing the ideal fan type.
The following are the noise level recommendations for different scenarios
- For a hospital, the noise level should be between 40-55 db
- For school, the noise must be within the range of 35-55 db
- The recording room must be within 20 – 30 db
- The ideal noise level for hostels and hotels is 30 – 55 db
- For malls, it is recommended to keep the noise between 45 – 55 db
- For offices, it must be within the range of 25 -40db
When selecting the HVAC fan, the professionals must take the installation location’s details and the permissible noise level standards into consideration.
Static Pressure
Since this is one of the essential factors to be considered, technicians are required to calculate the necessary parameters before choosing the suitable HVAC fan type within that pressure range for the installation.
Guaranteeing the HVAC System’s Reliability with AI-Powered Tools
Air quality is among the main factors that decides a building’s success when it comes to proper construction. This is where the construction companies put a lot of weight on inspecting the quality of airflow inside the structure they build. One tiny error or malfunction within the HVAC System’s fan network can lead to poor air quality, safety of the occupants and regulatory compliance, etc. Tigernix is introducing the best Fan Asset Solution to ensure your web of fans is in good health using the Artificial Intelligence power now. With its robustness, you can pave the way for an upgraded air management mechanism.
