Centrifugal vs Axial Fans

Industrial fan manufacturers play a crucial role in various industries. Yet, their exact function often needs to be clarified in the market. The term “industrial fan” lacks a precise definition, leading to confusion about its true purpose and application. This article aims to uncover the concept of centrifugal and axial fans, clearly explains what they are, and addresses several other related questions.

This discussion seeks to offer comprehensive insights into the world of industrial fans, ensuring that the reader gains a thorough understanding of their importance and usage. To delve deeper, we will explore these fans’ diverse roles in different industrial settings. Understanding the functionality and significance of industrial fans is essential for comprehending their impact across various sectors.


The Two Basic Types of Industrial Fans

Industrial fans come in two fundamental types: Axial and Centrifugal Fans. But these two categories encompass a wide array of fans and blowers, each falling under different classifications such as Industrial Blowers, Industrial Ventilation Fans, Exhaust Blowers, and Industrial Exhaust Fans. Terms like HVAC fans and blowers are also commonly used. Despite the variety of names and classifications, all these devices can be broadly categorised as axial or centrifugal fans.


1. Axial Flow Fan

Axial flow fan is commonly utilised for moving air. Imagine a ceiling fan or a small desk fan; these are everyday examples of axial flow fans. The key characteristic of regular and axial flow fans is that the air flows in a direction parallel to the fan’s rotor shaft. It is the axis around which the fan’s blades rotate.

In simpler terms, this fan type draws air from behind it and then pushes it out in front, in the same direction as the spinning blades. This is distinct from other fans.

High-speed axial fans are widely used for their simplicity and effectiveness in moving large volumes of air. They are often found when the primary requirement is significant airflow, such as ventilation systems, cooling computers, or large industrial applications.

Their design can vary in size, from tiny fans used in electronics to massive fans used in wind tunnels. Key technical aspects that interest those looking to research further include blade design, airflow rate, pressure generation, and efficiency.

Axial flow fan Diagram

2. Centrifugal Fan

Sometimes known as blower, this fan is commonly used in various settings and distinguished by its unique method of moving air. Unlike axial flow fans, where the air moves along the axis of the fan, the blower draws air into the centre of the fan and then expels it at a 90-degree angle.

The design of this fan is like a hamster wheel. It consists of a rotating set of blades and an impeller enclosed in a casing. The air enters the fan wheel through the central hole, is caught by the impeller blades, and is flung outward due to centrifugal force to the fan’s outlet.

This design allows centrifugal fans to generate higher pressures, making them suitable for applications that require air to move through resistance, like air conditioning systems, industrial ventilation, and various air pollution control systems.

Fans under centrifugal design are appreciated for their versatility in different performance conditions and ability to handle air with particulates. Key technical aspects for further research may include impeller design, efficiency, pressure head, and noise levels.

Centrifugal Fan Diagram

Comparing Centrifugal and Axial Flow Fans

When comparing a centrifugal to an axial fan, with equal flow and pressure, the former exhibits several distinct characteristics:

  • It features a smaller impeller diameter.
  • It generates higher dynamic pressure.
  • It operates at a considerably higher speed, both in terms of operating and specific speed (considering equal Q and P).
  • The peripheral speed is greater.
  • It has lower efficiency, leading to increased power consumption.
  • It tends to be noisier.
  • It is considerably more compact, lighter, and more cost-effective.

When comparing centrifugal and axial flow fans, the main factors are weight, operational speed, and noise levels. Fans manufactured axially can achieve similar airflow and pressure characteristics at higher operating and peripheral speeds than centrifugal fans.

However, there are limits to the stress that rotating parts can endure, which affects their speed. Consequently, centrifugal flow fans are generally more adept at generating higher pressures. A notable disadvantage of axial flow fans is their noise; they frequently require silencers to mitigate sound, whereas blowers typically do not need them.

Axial flow fans are commonly used in low-pressure environments (up to 100 mmWg). Regarding efficiency, they are comparable to centrifugal (or radial) fans, especially for large-sized fans.

Another advantage of high-speed axial fans is their design, facilitating easy system integration. They can seamlessly fit into existing pipelines as part of the ductwork. At the same time, centrifugal flow fans often necessitate more complex and costly installation.

Centrifugal flow fans can have a single width suction inlet (SWSI) or double width suction inlet (DWDI). A DWDI fan, with identical size, speed, and pressure specifications, can handle double the capacity and consumes twice the power of a SWSI fan. It’s important to note, however, that the casing size of a DWDI fan is not always double that of a SWSI fan.


Types of Axial Flow Fans

1. Tube axial Fans

Tube axial fans consist of a wheel positioned inside a cylindrical housing, designed with minimal clearance between the blade and housing to enhance airflow efficiency. These fans rotate faster than propeller fans and can operate under higher pressures, typically ranging from 250 to 400 mmWg. Their efficiency can reach up to 65%. Tube axial fans are well-suited for scenarios where high-efficiency airflow is needed.

Tube Axial Fan Diagram

2. Vane axial Fans

Vane axial fans are like tube axial fans but include additional guide vanes. These vanes help direct and straighten the airflow, increasing efficiency. Ideal for commercial and industrial applications, these fans are designed to handle large volumes of air at moderate to high pressures.

Vane axial fans are among the most energy-efficient options. They are broadly used for heat, smoke, fume removal, process drying, cooling, and general ventilation.

Vane Axial Fan Diagram

3. Propeller Fans

Operating typically at low speeds, these fans can move large volumes of air at low pressure, making them suitable for indoor exhaust and outdoor applications like air-cooled condensers and cooling towers. However, their efficiency is relatively low. They are sensitive to changes in static pressure, leading to significant airflow variation.

Propeller Fan Diagram

Specialised Axial Fans: Bifurcated Fans

Bifurcated fans are a unique type of axial flow fan designed to isolate the electric motor and support from the airflow. This separation is crucial in environments where the air contains corrosive elements or has high temperatures, as it protects the motor and supports it from damage.

This fan is typically used for extracting hot fumes in environments with high humidity and grease, such as kitchens, painting booths, furnaces, and foundries. Cross-ventilation for the electric motor or supports is often incorporated for high-temperature applications.

Bifurcated Fan Diagram

Understanding Industrial Fan Selection

Choosing the right industrial fan, whether centrifugal or high-speed axial fan, involves carefully looking at the needs of the place where the fan will be used and understanding the specific features of the fan you’re interested in. The fan supplier must share detailed information to ensure the fan matches the buyer’s needs.

The fan supplier’s job is more than just selling a product and understanding customer needs. This means figuring out how much air the fan needs to move (its flow rate) and how strong it needs to push this air (its pressure).

Customers need to know their system’s requirements, whether an axial flow fan or a centrifugal fan. The fan’s job is to move air or another fluid at a specific rate, measured by how much there is of it over time and at a certain pressure, often measured in Pa (Pascals) or mmWg (millimetres of water). This pressure is needed to push the air through any obstacles or resistance.

The fan gets power from an electric motor, but not all is transferred directly to the air. This is because not all machines are 100% efficient; there’s always some loss of power. So, the motor’s power to the axial or centrifugal fan is always more than what gets used to move the air. The efficiency of a fan is about how much of this power is successfully used to move the air.


Get in Touch with Us Today

Looking for the perfect industrial fan solution? Contact us now at +(65) 6451 6168 or email sales@jaredden.com.sg. JA Redden’s expert team is ready to understand your specific needs and guide you to the best choice. Don’t wait any longer to enhance your system’s efficiency with our top-quality axial and centrifugal fans. Reach out today—we’re here to help you every step of the way!

In Heating, Ventilation, and Air Conditioning (HVAC), the efficiency and effectiveness of a system largely hinge on the design and functionality of its cooling coils. Understanding the concept of coil circuiting is essential for anyone designing, maintaining, or operating HVAC systems. This blog aims to demystify the complexities surrounding coil circuiting and its impact on coil performance.


What Is Coil Circuiting?

Coil circuiting refers to arranging and connecting tubes or pipes within a chilled water coil or refrigerant coil. These circuits are pathways through which the chilled water or refrigerant travels. The design of these circuits significantly affects how the cooling medium absorbs heat from the air, influencing the overall efficiency of the heat exchange process.

The circuiting pattern chosen must balance the need for efficient heat transfer with practical considerations like pressure drop and physical space constraints. That’s why it is crucial to optimise the flow path to maximise heat exchange while minimising the impact on system performance. Careful selection of materials and design adjustments can further enhance the thermal efficiency within the given spatial limitations.


Cooling Coil Circuits

The heart of any HVAC system is its ability to control temperature and humidity, tasks primarily undertaken by this coil type. These coils contain the cooling medium that absorbs heat from the air, cooling and dehumidifying it. The effectiveness of this process is directly tied to the circuiting of the coils.

Properly designed circuiting ensures maximum contact between the air and the cooling medium, leading to optimal heat transfer. It also impacts the pressure and temperature distribution within the coil, further affecting the system’s performance.


Typical Circuiting Arrangements

Understanding the various circuiting arrangements in HVAC systems is crucial for optimising the performance of cooling coils. These arrangements, including full circuit, half circuit, quarter circuit, and double circuit, play a significant role in determining how effectively the system can transfer heat. Each type of circuit has its unique characteristics and applications.


1. Full Circuit

Full Circuit Diagram

The full circuit arrangement involves the refrigerant passing through the entire length of the coil in a single, continuous path. This design is straightforward and is typically used in smaller systems where the pressure drop is not a significant concern.

Full circuits are efficient for systems with a relatively low cooling load, providing a uniform cooling medium distribution across the cooling coil. However, in larger systems, this type of circuiting can lead to higher pressure drops and less efficient heat transfer.


2. Half Circuit

Half Circuit Diagram Cooling Coils

In a half-circuit arrangement, the coil is divided into two parallel paths. This setup reduces the length of each path the cooling medium takes, effectively halving the pressure drop compared to a full circuit.

Half circuits are beneficial in medium-sized systems where managing pressure drop is crucial for maintaining efficiency. This type of circuiting also allows for a more even distribution of the cooling medium. It can improve the cooling coil’s overall heat transfer capabilities.


3. Quarter Circuit Diagram

Quarter Circuit Diagram Cooling Coils

Quarter circuiting takes the concept of the half circuit further by dividing the coil into four parallel paths. This arrangement significantly reduces the pressure drop by shortening the cooling medium path. It is beneficial in larger systems where controlling pressure drop is essential for maintaining system efficiency and performance.

Quarter circuits can handle higher cooling loads more effectively, though they may require more complex manufacturing and design considerations.


4. Double Circuit

Double Circuit Diagram

The double-circuit arrangement involves two separate circuits within the same cooling coil. Each circuit operates independently, allowing for more precise control over the cooling medium flow and heat transfer. This type of circuiting is ideal for large and complex systems where different areas or zones may have varying cooling requirements.

Double circuits can optimise load management across the coil, improving efficiency and the system’s adaptability to varying conditions. These circuiting arrangements each have unique advantages and are chosen based on the specific requirements of the cooling system. Factors like the size of the system, the cooling load, and the desired efficiency play a critical role in determining the most suitable cooling coil circuiting type.


Determining the Right Number of Circuits

Selecting the appropriate number of circuits is a critical aspect of coil design. This decision depends on factors such as the required cooling capacity, the type of refrigerant, the available space, and the specific operational demands of the system. A higher number of circuits can enhance heat transfer efficiency but may increase complexity and cost. Conversely, fewer circuits can simplify the system but might not deliver the desired cooling performance.


Optimising Coil Performance Through Circuiting

Effective circuiting enhances the performance of cooling coils and contributes to the overall energy efficiency of the HVAC system. Engineers must consider airflow patterns, cooling medium type, and load variations to optimise the circuiting design. Advanced computational tools and simulation software are often employed to predict and fine-tune the performance of different circuiting arrangements.


Maintenance and Longevity of Hydronic Cooling Coils

Regular maintenance is crucial for sustaining the performance of coil type. Over time, factors like dust accumulation, corrosion, or refrigerant leakage can impact the effectiveness of the coil circuiting. Routine inspections and cleaning are essential to ensure that the coils and circuiting remain in optimal condition.

Additionally, preventive measures such as regular checks for leaks, ensuring proper refrigerant levels, and monitoring for any signs of wear and tear can significantly prolong the life of cooling coils. Regular maintenance enhances the system’s efficiency and helps avoid costly repairs and downtime. The importance of adhering to a scheduled maintenance plan and using qualified professionals’ services cannot be stressed enough. They are cornerstones to keeping your HVAC system running smoothly and efficiently.


The Significance of Coil Circuiting in HVAC Efficiency

The design and configuration of coil circuiting play a pivotal role in the functioning of HVAC chilled water coils or refrigerant coils. Understanding the intricacies of circuiting helps in designing more efficient and effective systems. Whether you are an HVAC professional, a system designer, or simply someone keen on understanding the workings of cooling systems, grasping the fundamentals of coil circuiting is invaluable.

Through careful design, regular maintenance, and an understanding of the specific requirements of each application, one can ensure that the cooling coils in an HVAC system perform optimally, providing comfortable indoor environments while keeping energy consumption in check.


Enhance Your HVAC System Today

For expert advice, system design assistance, or maintenance services for your HVAC cooling coils, don’t hesitate to reach out. Contact JA Redden at +(65) 6451 6168 or email sales@jaredden.com.sg. Our team of professionals is ready to provide you with tailored solutions to meet all your HVAC needs. Let’s work together to ensure your system performs at its best!

Ventilation fans in Singapore are an indispensable component of the industrial field. They play a
pivotal role in maintaining air quality, regulating temperature, and ensuring safety by removing
airborne contaminants. Whether you’re an industry professional or simply curious about how
these systems work, this article will take you to the definitions of airflow versus static pressure,
their relationship, and the critical role of impedance.


Air Flow-Static Pressure Character Graph: Understanding Fan Performance

Manufacturers use the air flow-static pressure character graph, like a speed-torque curve in
motors, to display fan performance, particularly indicating the sources of airflow and static
pressure specifications.

Airflow Table

For some customers, this representation of ventilation products can appear quite unfamiliar. Many
customers often select fans based on their dimensions and airflow alone. However, deeper insight
is necessary to gauge how a fan will perform accurately in real-world conditions.


Max Air Flow Max Static Pressure
m³/min CFM Pa inH2O
21 742 320 1.28
25 883 390 1.57
25 883 410 1.65
24 848 340 1.36
24 848 1.45 24
21 742 310 1.24
24 848 360 1.45
21 742 320 1.28
24 848 360 1.45


In the table detailing ventilation fan specifications, “Maximum Air Flow” and “Maximum Static
Pressure” are the key performance metrics.


refers to the air volume a fan can circulate over a given period, commonly measured in
cubic meters per minute (m³/min) in metric units or cubic feet per minute (CFM) in imperial units.

Consider a fan with a capacity of 5 CFM in a 5 ft x 5 ft x 5 ft enclosure; theoretically, it would take
about 25 minutes to ventilate the hot air completely from this space. However, the actual
ventilation process is more complex

Static pressure

, however, represents the ventilation fan’s ability to generate air pressure within
an enclosure. This is typically measured in Pascals (Pa) or inches of water (inH2O). A Pascal,
named after Blaise Pascal, is the SI unit for pressure, equivalent to one newton per square meter.

static and airflow table

Meanwhile, inches of water gauge (inH2O) measure the pressure exerted by a one-inch-high
column of water at a specific temperature (4 °C, where water is densest) and is approximately
equal to 249.082 Pascals.

It’s crucial to understand that fans cannot simultaneously deliver their maximum airflow and static
pressure values. The full specifications for each are distinct and cannot be achieved concurrently.

Airflow and static pressure in ventilation fans exhibit a negative correlation, meaning that an
increase in one typically leads to a decrease in the other and vice versa. This relationship is crucial
in understanding how fans perform in different scenarios, particularly ventilating an electronics


Let’s examine three illustrative examples:

1. Open Enclosure Scenario

Here, the enclosure is open at one end, allowing unobstructed airflow from the fan. This situation
facilitates maximum airflow with zero static pressure, as all the air is expelled smoothly from the
other end.

Arrow air flow table

2. Partial Obstruction Scenario

The enclosure is almost sealed in this ventilation fan setup, save for a small exhaust hole smaller
than the air intake. This limitation in the exhaust size impedes airflow, leading to a build-up of air
inside the enclosure, thereby increasing static pressure. As a result, airflow is reduced from its
maximum due to the heightened static pressure.

Air Intake Table

3. Fully Sealed Enclosure Scenario

The enclosure is entirely closed in this example. Air flowing into the enclosure increases the static
pressure since the air has no exit path. Once the static pressure exceeds the fan’s specification,
no additional air can be introduced, even if the ventilation fan continues to operate. Thus, at
maximum static pressure, the airflow volume drops to zero.

Ventilation Fan Diagram

In practical terms, scenarios 1 and 3 are extremes not typically encountered in real-life
applications. Most ventilation scenarios, especially in electronics enclosures, closely resemble
example 2.

The double chamber method is often employed to effectively illustrate the relationship between
airflow and static pressure on a graph. This method helps visualise how a fan’s performance
varies under different air resistance and pressure build-up conditions.


The Importance of Impedance

Determining the precise airflow and static pressure requirements in a ventilation fan system
hinges on understanding impedance. Impedance, in the context of airflow, refers to the resistance
the air encounters as it moves. It can arise from various sources such as electronic components,
walls, or any obstructions in the airflow path. This impedance ultimately dictates the actual airflow
and static pressure a system will experience.

The’ square law’ is often applied to quantify this concept, particularly in forced air cooling
applications. This principle states that static pressure varies as the square of the change in CFM
(Cubic Feet per Minute).

In essence, minor alterations in airflow can result in disproportionately large changes in static
pressure, highlighting the importance of accurately assessing impedance for effective system

The equation below can quantify static pressure in ventilation fans in Singapore:





    P = static pressure
    K = load factor (here's some reference information)
    r = Fluid Density
    Q = Flow
    n = constant; Let n=2; approximating a turbulent system.

Impedance static pressure and airflow relevance to ventilation

Understanding Impedance

The impedance curve in the impedance graph depicts distinct lines representing various
impedance levels. These lines are crucial for understanding how impedance affects fan

On the other hand, the performance curve simultaneously represents airflow and static pressure.
The point where the impedance and performance curves meet indicates a scenario with different
impedance levels.

In other words, the actual airflow and static pressure a ventilation product will achieve in any given
system are identified at the intersection points of these impedance curves with the fan’s
performance curve.

Determining system impedance can sometimes be challenging. In such situations, a practical
approach is to assume that the actual airflow will be approximately half of the fan’s maximum
capacity. Therefore, choosing a fan that can deliver twice the airflow needed for your specific
requirements is advisable.

Beyond simply selecting the right ventilation fan, successful ventilation design for an enclosure
also involves other critical factors. These include the size and location of intake and exhaust holes
and the placement of internal components.

To illustrate how these elements influence the airflow of ventilation fan in Singapore, smoke traces
airflow patterns visually. This demonstration highlights the impact of varying intake hole sizes and
dividers within the enclosure, providing a clearer understanding of practical ventilation design

Incorporating accessories like filters, screens, or finger guards can significantly enhance the
durability and longevity of fans in environments prone to dust or moisture. But it’s important to
note that these additions can also alter the fan’s airflow and static pressure properties.

Find More Ventilation Products at JA Redden

Visit JA Redden or contact +(65) 6451 6168. You may also email sales@jaredden.com.sg. Only
believe an expert’s insights when it comes to your ventilation requirements. Talk to us at JA
Redden today!

Many axial flow fan manufacturers said that air blowers are devices used to generate airflow for improving ventilation. Although they are often seen, these equipment are seldom understood in their entire technicality. In this blog, let’s take you on an in-depth discussion of the principles and everything you need to know about air blowers.

The Essence of Air Blowers: More Than Just Moving Air

Air blowers are intricate devices pivotal in modern industrial and commercial applications. At its most basic level, these equipment are designed to move air. However, an air blower fan’s functionality and importance stretch beyond this simple description.

Such devices utilise an impeller, a crucial rotating component, to increase the speed and volume of the air. This impeller is driven by a motor, which enables the blower to draw in air and expel it at a high velocity. This process is central to the blower’s ability to offer controlled and directed airflow. This feature sets it apart from traditional fans.

In industrial settings, air blowers are indispensable. They are used to cool heavy machinery and electronic equipment, prevent overheating, and ensure operational efficiency. In the commercial field, they are vital in HVAC systems, contributing to effective heating, ventilation, and air conditioning, thus maintaining comfortable indoor environments.

Air circulation, another key function of air blower fans, is crucial in maintaining air quality. By continuously moving air, these blowers help filter and purify the air, essential in environments like laboratories and hospitals where air quality is imperative.

Moreover, air blowers are integral in various manufacturing processes. They are used in pneumatic conveying systems to transport materials, in drying processes to remove moisture, and even in cleaning applications where directed air is used to remove dust or debris.

Their varied designs and types further highlight the versatility of air blowers, each tailored to specific applications and requirements. From large, industrial-grade blowers to compact units designed for tight spaces, the range of available options ensures an air blower fan is suitable for virtually any situation.

Axial Air Blowers

Axial air blowers excel in cooling large volumes of air with high efficiency and low pressure. Their tube design makes them suitable for applications like wind tunnels and specific HVAC systems. Axial air blowers are particularly effective when large-scale air circulation is needed without high pressure.

Axial Air Blower Image

Technical Considerations for Optimal Performance

The performance of an air blower is not solely dependent on its type and application. Still, it is also significantly influenced by various technical factors. Understanding these elements is crucial to ensure that your air blower operates at peak efficiency, offering the best balance of power, durability, and energy efficiency.

1. Impeller Size and Design

The impeller is the heart of an air blower fan, and its size and design are pivotal in determining its pressure and airflow capabilities. Larger impellers can generate more pressure, making them suitable for robust air movement applications. Conversely, smaller impellers are ideal for applications where space is limited, and less pressure is needed. The blades’ design, angle, and curvature also play a crucial role, affecting their performance from air volume to noise levels.

2. Impeller-to-Cut-Off Distance

This refers to the space between the impeller and the point where the air begins to exit the housing. It’s a critical factor for ensuring efficient air movement and preventing backflow, which can reduce the blower’s efficiency. Precise calibration of this distance is essential to maximise performance and minimise energy consumption.

3. Heat Emission

All air blower fans generate heat, but the amount can vary significantly based on the blower’s design and workload. Higher pressure operations tend to produce more heat, affecting the blower’s efficiency and lifespan. Understanding and managing heat emissions is crucial, especially in sensitive environments where excess heat can be detrimental.

4. Environmental Factors

The operating environment plays a significant role in the performance of an air blower. Factors such as ambient temperature, humidity, and altitude can impact air density and flow, necessitating adjustments in blower specifications. For instance, air blower fans at high altitudes must compensate for thinner air to maintain performance.

5. Configuration and Wiring

The way air blowers are configured and wired can significantly affect their performance. The arrangement must be carefully considered whether set up in series for increased pressure or parallel for greater volume. Proper electrical wiring is also crucial to ensure that the blower operates safely and at its intended capacity.

Why Expert Advice Matters

Given the complexity and variety of factors that influence the performance of air blowers, seeking expert advice is invaluable. Axial flow fan manufacturers specialists have the knowledge and experience to navigate these technical aspects. They can provide insights on the best impeller design, appropriate configurations, and suitable environmental considerations for your needs.

Consulting with experts ensures that your air blower is optimised for performance and that it operates efficiently, saving energy and reducing costs in the long run.

Air blower fan

Get in Touch for Expert Guidance

For professional advice and a wide range of solutions in axial flow fan manufacturing and other air blower fans, please contact +(65) 6451 6168 or email sales@jaredden.com.sg. You may also visit JA Redden’s website. Remember, the right air blower not only enhances the efficiency of your application but also contributes to energy savings and operational effectiveness.

The process of ventilating a building involves the removal of stale or unpleasant air and its
replacement with fresh air. This essential process, necessary in various settings, always follows
the same basic principle: expelling unwanted air and drawing in clean air. The specific fan type
and the rate of airflow, measured in cubic feet per minute (CFM), vary depending on the
application. Other important factors include the resistance to airflow, known as static pressure
(SP), and the fan’s noise level, measured in decibels A (dBA).

Selecting an appropriate exhaust fan in Singapore for a specific function can be challenging,
especially when unsure of the required model or air capacity. Because of this, it becomes necessary to
engage in fan specification, a process that is not an exact science but can be approached
confidently when the fan’s intended use is clearly understood.

For proper fan selection, four key parameters must be determined: the model of the fan, the airflow
rate in CFM, the system’s static pressure, and the acceptable noise level in the environment.


1. Fan Model

Various models of exhaust fans in Singapore are available, each designed to move air effectively
from one space to another. Due to the wide range of fan applications, manufacturers offer diverse
models with advantages for specific uses. The challenge for users lies in identifying the model
that best meets their requirements. Here are some key considerations:


Direct drive or belt drive?

Direct drive fans are cost-effective and require minimal maintenance for low-volume air movement
(2,000 CFM or less) and low static pressure (0.50 inches or less). Some fans can be adjusted
using a speed control to alter the airflow. On the other hand, Belt drive fans are more suitable for
moving larger volumes of air (over 2,000 CFM) and for higher static pressures (above 0.50
inches). They feature adjustable pulleys that allow a 25% change in fan speed and airflow. Beltdriven fans are typically preferred for operating temperatures above 50º C (122º F).


Axial or centrifugal?

Axial fans, resembling propellers, are economical for moving large volumes of air (over 5,000 CFM) at low static pressures (0.50 inches or less). However, since the motors are usually placed
in the airstream, they are best used where the air is relatively clean and not too hot, with maximum
temperatures around 40º C (104º F). Centrifugal fans, in contrast, are more efficient at handling
higher static pressures and are quieter than axial fans. Many centrifugal fan models are designed
with motors outside the airstream, making them suitable for moving contaminated or high temperature air.


Roof, wall, or duct?

Fans are designed for three common mounting locations: roofs, walls, or ducts. The fundamental
components of the fan remain the same regardless of the location; only the housing changes to
facilitate installation. The desired airflow pattern and the building’s physical layout determine the
optimal location for a fan. Assessing the building’s structure and visualising the desired air
movement makes the best placement for the fan clear.


2. Cubic Feet per Minute (CFM) of Airflow

When selecting an exhaust fan in Singapore, it’s essential first to identify the fan type and then
calculate the volume of air that needs to be exchanged. Local building codes typically guide the
air changes required for adequate ventilation. These guidelines generally suffice for most situations.

However, the necessary airflow may fall outside this suggested range in extreme conditions. To
accurately determine the number of air changes needed, consider factors such as the geographic
location and the usual intensity of use in the area.

Choose a lower number within the specified range in hotter climates or areas with heavier usage
to facilitate faster air exchange. Conversely, a higher number within the range may be adequate
in moderate climates or spaces with lighter use.

To calculate the volume of a room, multiply its length, width, and height. Then, apply the following
formula to ascertain the cubic feet per minute (CFM) required for sufficient ventilation of the space:

𝐶𝐹𝑀 = 𝑅𝑜𝑜𝑚𝑉𝑜𝑙𝑢𝑚𝑒 ÷ 𝑀𝑖𝑛/𝐶ℎ𝑎𝑛𝑔𝑒

Recommended Air Exchange Rates for Effective Ventilation


Area Minutes to Change
Assembly Hall 3 to 10
Attic 2 to 4
Auditorium 3 to 10
Classroom 4 to 6
Corridors/Halls 6 to 20
Dormitories 5 to 8
Engine Room 1 to 3
Factory 2 to 7
Garage 1 to 10
Generator Room 2 to 5
Gymnasium 3 to 8
Kitchen 1 to 5
Laboratory 2 to 5
Machine Shop 3 to 6
Meeting Room 3 to 10
Office 1 to 8
Packing House 2 to 5
Residence 2 to 8
Restaurant 5 to 10
Toilet 5 to 7
Warehouse 3 to 10


3. Static Pressure

Accurately measuring static pressure is essential for correctly selecting an exhaust fan in

Static pressure in fan systems is measured in inches of water gauge, where one pound per square inch is equivalent to 27.7 inches of static pressure (SP). Typically, the static pressure in these systems is less than 2 inches SP or 0.072 psi.

The accompanying illustration shows how a manometer measures static pressures in the
ductwork. A differential in pressure between the duct and the atmosphere causes the water levels in the manometer to vary. This variation represents the static pressure, measured in inches of water gauge.

exhaust fan diagram

In the example of the exhaust fan, the air is pulled upward through the ductwork, creating a low pressure area at the top of the duct. This principle is like how liquids are drawn up through a straw. The static pressure that the fan needs to overcome depends on several factors, including the air velocity within the ductwork, the amount of bends in the duct, other elements that resist airflow, and the duct length. For well-designed systems with adequate makeup air, the following guidelines can be used to estimate static pressure.


Static Pressure Guidelines for Exhaust Fans in Singapore

  • Non-Ducted Systems: 0.05 inches to 0.20 inches
  • Ducted Systems: For every 100 feet of duct, the static pressure should be between 0.2
    inches and 0.40 inches, provided the air velocity in the duct is between 1,000 feet per
    minute and 1,800 feet per minute.
  • Fittings: Each fitting (elbows, registers, grills, dampers, etc.) adds 0.08 inches to the static
  • Kitchen Hood Exhaust: The static pressure ranges from 0.625 to 1.50 inches

It’s crucial to note that the static pressure requirements are greatly influenced by the volume of makeup air supplied to the space. Inadequate makeup air can lead to increased static pressure and a decrease in the volume of air being exhausted. It’s crucial to ensure that for every cubic foot of air exhausted, an equivalent cubic foot of air is supplied.


4. Loudness Limit

When selecting an exhaust fan in Singapore, it’s essential to consider the noise level it generates.
In the fan industry, noise is commonly measured in sones. To put this into perspective, one sone
is roughly as loud as a quiet refrigerator heard from a distance of 5 feet in a typical room. Sones
are a linear measure of sound intensity, meaning a fan producing ten sones is perceived as twice
as loud as one producing five sones.

For choosing a fan that suits your needs, refer to a sone chart to find a noise level acceptable for
your application. Generally, it is advisable to select a fan whose sone rating falls within the
recommended range for its intended use.

Recommended Limits for Room Loudness

                                           Room Type dBA
Private homes (rural and suburban) 32 to 48
Conference rooms 36 to 51
Hotel rooms, libraries, movie theatres, executive offices 38 to 54
Schools and classrooms, hospital wards, operating rooms 41 to 58
Court rooms, museums, apartments, private homes (urban) 44 to 60
Restaurants, lobbies, general open offices, banks 48 to 64
Corridors and halls, cocktail lounges, washrooms and toilets 51 to 67
Hotel kitchens and laundries, supermarkets 56 to 72
Light machinery, assembly lines 64 to 80
Machine shops 67 to 84
Heavy machinery 67 to 84


Expert Ventilation Solutions from JA Redden

If you’re looking to ensure optimal ventilation in your space with the right exhaust fan, look no
further than JA Redden, your trusted HVAC expert. Our team provides you with tailored
solutions that meet your specific needs.

You’re welcome to register in our Download form, via the below link, to receive a free QuickFan selection software that is easy to use and loaded with various tools to assist in your design & calculation.


Ventilation Project Chart

At JA Redden, we understand the importance of proper air circulation, noise levels, and energy
efficiency. Contact us today on +(65) 6451 6168 or email sales@jaredden.com.sg to find the
perfect exhaust fan solution and experience the difference a professionally selected and
installed system can make in your environment. Trust JA Redden for all your HVAC needs—
where quality air meets quality service.

The Heating, Ventilation, and Air Conditioning (HVAC) industry constantly evolves with
innovations aiming to improve energy efficiency, system performance, and overall user
satisfaction. One such significant innovation in the HVAC industry is the Electronically
Commutated (EC) fan. By understanding the functionality and benefits of the EC fan, users can
make informed decisions that could lead to long-term savings and optimised performance.

What Is an EC Fan?

An EC fan is technologically advanced, powered by brushless, permanent magnet DC motor and
onboard electronics that control the fan rotor. Unlike the traditional asynchronous AC motors,
which utilise belt technology, taking up more space and requiring frequent maintenance due to
wear and tear, EC fan motors offer a compact and efficient solution. These asynchronous AC
motors drive traditional fans in the HVAC systems, particularly within the air handling unit. This
not only make installations more complicated but also leads to decreased energy efficiency. But
with permanent magnet DC motors, there is higher efficiency and more precise control.

Ec Fan

How EC Fans Affect HVAC Systems

An HVAC system’s primary objective is to regulate air temperature, ensuring a comfortable
environment in large office spaces or specific controlled environments like marine enclosures at
zoos. To achieve this, consistent and rapid air movement is paramount.

Traditional AC motors, previously employed to drive air, operated mainly at full power, limiting
their efficiency and adaptability. With the advent of EC fans, the scenario has changed
dramatically. EC fans maintain refrigerant pressure consistently, reducing strain on the
compressor and ensuring energy savings, and operate quietly due to enhanced commutation
methods and aerodynamic impellers. In addition, the precise speed control of EC fans allows for
adjusting the air volume as needed, ensuring the air handling unit operates optimally.

Control Fan Diagram

Advantages of Utilising EC Fan Technology Over Traditional Fan and Motor

EC fans present several distinctive advantages over conventional fan and motor technologies.
Let us delve deeper into these benefits:

1. Enhanced Energy Efficiency

One of the standout features of EC fan kits is their profound energy-saving capabilities. Unlike
traditional fans, EC fans are designed to maintain impressive efficiency even at typical operational
speeds. This high-efficiency results in considerable energy conservation and long-term financial

2. Longevity and Reduced Maintenance

The design intricacies of EC fans make them relatively maintenance-free. For instance, they
eliminate the need for periodic belt replacements, a common maintenance task with traditional
AC motors. Furthermore, the low heat generation from the best EC fans augments the longevity
of its components, ensuring that they outlast their conventional counterparts.

3. Adaptable Speed Control

EC fans come equipped with the ability to vary their speed based on the requirements. This
adaptability not only helps reduce the noise emitted by the motor but also ensures that the fan
can adjust its air movement in sync with changing demands while maintaining energy efficiency.

4. Inherent Protection Mechanisms

EC fans motors are integrated with onboard electronics that provide safeguarding features. This
built-in protection eliminates the need for additional external protective devices, simplifying the
overall setup.

5. Advanced Remote Monitoring

The technological advancements from EC fan manufacturers have incorporated features like
analogue and digital communication ports. This addition allows users to monitor and control the
fan operations remotely, thus offering enhanced control and customisation opportunities.

6. Space-Saving Design

The compact design of EC fans, attributed to their smaller motor size, makes them a perfect fit
for retrofitting tasks. This means that old, energy-draining fans can be conveniently replaced with
EC fans without the logistical challenges of installing entirely new equipment.

7. Optimal Temperature Regulation

Another feather in the cap of EC fan motors is their ability to operate at relatively cooler
temperatures when juxtaposed against traditional AC motors. This feature reduces the heat
contributed to the airflow and extends the life of its components.

Prevailing Four Benefits of EC Fans

EC fan kits emerge as a formidable alternative when considering ventilation solutions, offering
numerous benefits over their traditional counterparts. These advantages range from unparalleled
efficiency to versatile designs. Accompany us as we delve into the specifics of these advantages:

1. Superior Energy Efficiency

One of the standout features of EC fans is their ability to achieve unparalleled energy efficiency,
reaching levels as high as 90%. This high efficiency is primarily due to the secondary magnetic
field from permanent magnets. Significant energy conservation is achieved by eliminating the
need for energy to generate this magnetic field, leading to reduced operational costs.

2. Precise Operational Control

A remarkable aspect of EC fan motors is the integration of printed circuit boards into their design.
This technology gives users granular control over the fan’s functions, allowing for precise tuning
to ensure maximum efficiency. This adaptability ensures that the fan delivers optimal
performance, irrespective of the diversity of applications it employs.

3. Durable and Reliable

One notable difference between EC fans and many traditional fans is the absence of carbon
brushes. These brushes, over time, can lead to wear and tear, decreasing the fan’s lifespan.
Furthermore, EC fan kits generally operate at cooler temperatures, which reduces the strain on
components, further enhancing their reliability. Together, these features ensure that EC fans
boast an extended service life, making them a sustainable choice for long-term applications.

4. Compactness Coupled with Versatility

EC fans are not just about efficiency and durability; they also bring a design advantage. Being
considerably lighter than many AC motors, they are conducive to superior airflow despite their
compact stature. This characteristic makes them particularly beneficial in scenarios where space
is at a premium, offering an efficient solution without compromising space.

The Future of Ventilation: Embracing EC Fan Technology

Embracing Electronically Commutated (EC) fans in HVAC systems marks a pivotal shift towards
cutting-edge ventilation solutions. With many benefits overshadowing conventional technologies,
EC fans symbolise the next phase of efficient, eco-friendly, and optimised HVAC advancements.
Whether rejuvenating an existing system or inaugurating a new setup, integrating EC fans
assures enduring advantages and guarantees a commendable return on investment, setting the
stage for a future-proofed ventilation approach.

Furthermore, adopting EC fan motors goes hand in hand with the broader trends of smart
technology integration and automation in building management systems. As infrastructures
become increasingly intelligent and interconnected, the demand for components that can
seamlessly integrate, communicate, and adapt becomes paramount.

With their advanced remote monitoring capabilities and precise operational controls, EC fans are
not just a response to this demand but a proactive step towards shaping a future where HVAC
systems are more efficient and innovative. The potential for scalability, adaptability, and
automation offered by EC fans makes them an invaluable asset for any forward-thinking facility
manager or property developer. By embracing EC fan technology, we’re optimising for the present
and paving the way for a smarter, more sustainable future in ventilation.

3 ec fan

Elevate Your Ventilation with JA Redden

At JA Redden, we prioritise delivering high-quality ventilation solutions. Sourced from world-
renowned manufacturers, our EC fans are designed to meet the exact standards of today’s
HVAC applications. With a legacy of innovation spanning Air Handling Units, Energy Recovery
Wheels, Mechanical Ventilation, and Industrial Fans, we are committed to offering products that
match your needs.

Choose JA Redden for unparalleled quality and expertise in EC fan technology. Explore our
official website at www.jaredden.com.sg. You may also call +(65) 6451 6168 or email

Singapore’s climate, characterised by soaring temperatures and high humidity, necessitates air-conditioning systems that are both effective and energy efficient. The energy recovery wheel (ERW) emerges as a front-runner. Beyond meeting cooling demands, this innovative system underscores energy conservation and indoor air quality. It meets Singapore’s dedication to sustainable living.

How Does an Energy Recovery Wheel Work?

The energy recovery wheel is often emphasised as a contemporary energy solution. In our hot & humid region, we sometimes known it as a heat recovery wheel. This HVAC component is often used to capture and recycle energy typically lost through the exhaust ventilation.

Picture a segmented wheel meticulously rotating between the expelled indoor air and the fresh air drawn from the outdoors. This wheel has the capacity to seize both the temperature (sensible heat) and moisture (latent heat) from the outgoing air. As its rotation continues, it then transfers the captured energy onto the fresh incoming air. The upshot? There is a drastic reduction in the burden shouldered by the primary air-conditioning units.

Energy Recovery

Benefits of Using an Energy Recovery Wheel

The benefits of the energy recovery wheel are many, offering incredible advantages to both the user and the environment.

1. Energy Savings

Singapore’s warm and humid climate necessitates continual cooling solutions, turning air-conditioning from a luxury to an essential need. Given the weather, energy consumption can surge, leading to high electricity bills.

Here’s where the energy recovery wheel comes to the rescue. This technology captures energy typically wasted during the ventilation process and repurposes it, thereby trimming the need for fresh energy. This results in a considerable dip in energy consumption and, by extension, lower utility bills, offering economic relief to residents and businesses alike.

2. Reduction in the Size of Heating and Cooling Systems

An efficient ERW doesn’t just save energy; it optimises system sizes. When the energy recovery wheel shoulders a significant portion of the heating and cooling duties, the Primary Air Handling Units can afford to be leaner and more compact. This translates not only to direct cost savings due to smaller equipment but also to more streamlined and aesthetic installations that are space-savvy. Property owners can then utilise this saved space for other purposes or maintain a less cluttered ambience.

3. Improved Indoor Air Quality

The role of the ERW extends beyond mere temperature modulation. In a place like Singapore, where humidity is often in the higher brackets, managing moisture levels indoors is paramount. The energy recovery wheel excels in this domain, ensuring consistent ventilation and balancing indoor humidity.

By preventing moisture build-up and facilitating optimal air exchange, it mitigates the proliferation of mould, mildew, and other indoor pollutants. The outcome is twofold: a fresher indoor atmosphere and a reduced health risk from airborne contaminants.

4. Environmental Impact

In the broader perspective of global environmental conservation, every action taken towards energy efficiency is a step in the right direction. The energy recovery wheel is an environmentally friendly component. By reducing the need for new energy generation, it essentially reduces greenhouse gas emissions, aligning with Singapore’s eco-friendly initiatives.

For stakeholders invested in sustainability and championing the green building movement, integrating an ERW not only amplifies their energy conservation efforts but also underscores their commitment to an environmentally responsible ethos.

In essence, the energy recovery wheel offers a harmonious blend of economic, environmental, and health benefits, making it a compelling choice for those aiming to upgrade their space’s cooling and ventilation systems.

Factors to Consider When Installing an Energy Recovery Wheel

Choosing to integrate an ERW into your building infrastructure is not a trivial decision. It calls for careful evaluation and consideration of several determinants. Here are crucial aspects to consider:

1. Building Size and Usage

The scale and functionality of a building often dictate the suitability of an energy recovery wheel. For instance, a petite cafe with limited daily air conditioning usage might not fully harness the potential benefits of an ERW.

Contrast this with large commercial spaces like shopping malls, where the incessant need for air-conditioning couples with extensive square footage. Here, the ERW can demonstrate substantial energy savings and operational efficiency. It’s imperative, therefore, to align the ERW’s capabilities with the building’s demands, factoring in its size and primary purpose.

2. Climate and Location

On the face of it, Singapore’s humid and warm climate seems an ideal candidate for heat recovery wheels. This technology thrives in environments where air conditioning systems work around the clock. Some things must be considered when integrating the ERW into these systems.

The orientation of a building, for example, determines the intensity and duration of sun exposure it receives, which in turn influences its cooling requirements. Additionally, buildings nestled amidst greenery or near water bodies might have different microclimates than those in more urbanised settings. These affect the thermal efficiency of a heat recovery wheel, necessitating a thorough assessment of the building’s locale.

3. Budget and Return on Investment

The financial aspect of integrating an ERW is multi-dimensional. The upfront cost might seem high, yet this investment should be gauged with respect to potential long-term dividends. In a region like Singapore, where energy costs can increase rapidly due to incessant cooling demands, the savings accrued over the years from a more efficient system can be substantial.

It’s not just about direct energy savings either; reduced wear and tear on primary HVAC components, stemming from the supportive role of the ERW, can also extend equipment life and curtail maintenance expenses. When contemplating this investment, it’s crucial to run a comprehensive cost-benefit analysis, ensuring that the ERW’s potential returns justify its initial cost.

4. Existing HVAC Systems

It’s crucial to ensure that current HVAC systems can integrate seamlessly with an energy recovery wheel. Some older HVAC configurations might need to be equipped for ERW integration, necessitating modifications or upgrades. This can impact both the cost and feasibility of the installation.

Conversely, newer HVAC systems might be designed with ERW compatibility, making integration smoother. Before committing to this technological addition, a thorough system compatibility check, ideally undertaken by HVAC professionals, is crucial.

Remember, while the energy recovery wheel is a promising technology, its advantages manifest when matched with the right environment and requirements. Making an informed decision is vital for reaping its full benefits.

Harnessing the Power of the Energy Recovery: Why JA Redden is Your Go-To Expert

The array of benefits that an ERW offers, from monetary savings to ecological gains, is enticing. Yet, there needs to be proper approach before integrating one. Deliberation, consultation, and tailored evaluations pave the way. And when in doubt? Industry professionals are ready to guide you. Talk to JA Redden and get more insights about ERW. The Heat Recovery Wheel can also be designed with split-casing to facilitate delivery. Our website also has an array of HVAC products to choose from. Explore now!

Folding Energy Recovery Wheel

Identifying the omnipresent risk of flammable gases, vapours, or dust in a hazardous atmosphere is essential to ensure the safe operation of these crucial plants. A Hazardous Area Classification in the risk areas is assessed, and the substances posing the hazard must be defined to select the appropriate type of Explosion-Proof Fan required.

The level of risk is represented by classifying the hazardous area as Zone 0, Zone 1 or Zone 2 (for gas, vapour and mist atmospheres) or Zone 21 or Zone 22 for dust atmospheres. The Explosion Gas Group and Ignition Temperature of flammable substances are also clearly defined.

Explosion Risk Zone

An Explosion-Proof Fan installed in a hazardous area must be qualified with the appropriate classification and protection. Designed to avert potential ignition sources, such as sparks or extreme temperatures, they prevent volatile atmospheres from igniting. Their pivotal role extends beyond safeguarding infrastructure, as they are also essential in protecting lives.

This article will discuss how the ignition source control is classified with the various Methods of Protection in an Explosion-Proof Fan. Two common designations of these protective devices are Exd and Exe. Delving deeper into these classifications will provide a clearer understanding of their significance and applications.

Exd: Explosion Proof Fan

Labelled ‘Exd’ or ‘flameproof’, these spark resistance fans have an Exd motor and a flameproof casing. This protection type contains any explosion produced inside the motor casing to propagate outside. They’re not about preventing an internal explosion; instead, they focus on containing it, ensuring no escalation to an external calamity. Especially in regions where explosive atmospheres are common, Exd fans come into play, assuring that potential equipment malfunctions leading to sparks remain isolated and preventing them from igniting the surrounding hazardous area.

The Exd motor of our Explosion-Proof Fan is of ATEX category II 2G, and it is suitable for ATEX Zones 1 and 2. Installation is easy because the user only needs to connect the power cables inside the connection box using flameproof cable glands, and standard motor protections are necessary outside the hazardous area. When this Explosion-Proof Fan is used with a frequency converter, the motor must be supplied with a PTC thermistor for overcurrent protection.

Exd protection is commonly used in areas with a high risk of explosive gas or vapour presence, such as chemical plants, refineries, and offshore oil platforms.

Exe: Increased Safety Fan

The Exe designation symbolises ‘increased safety’. As the name suggests, the motor of this Explosion-Proof Fan has an increased safety construction. This Exe protection type prevents any spark during the motor’s starting, operation or malfunction to avoid explosion sources in the motor.

The Exe motor is ATEX category II 2G, suitable for ATEX zones 1 and 2. Installation is more complicated as the user must connect power cables inside the connection box using increased safety cable glands, and a specially certified protection switch needs to be installed outside the hazardous area.

Their foremost defence line involves eradicating all probable ignition sources. They function below the ignition temperature of the surrounding explosive atmosphere, ensuring explosion conditions aren’t met. Their design elements include exceptional insulation to prevent electrical issues, firm connections to diminish spark risks, and, often, spark-resistant materials to mitigate ignition chances further.

Exe protection is often used in areas where the risk of explosive atmospheres is present. Still, the likelihood of internal explosions is low. It is suitable for many general-purpose electrical installations in hazardous areas.

Exd vs. Exe: A Comparative Deep Dive

Exd and Exe fans, critical components in the Explosion-Proof Fan lineup, are engineered with safety as their primary objective. However, their methodologies are different. It’s not a simple matter of picking one over the other. This choice is intricately influenced by various factors determining the potential for explosive incidents.

Here are the factors to consider:

  1. Nature of the Risk: The type of explosive material is crucial when choosing an Explosion-Proof Fan for your facility.
  • Gas: Environments with gaseous compounds demand vigilant monitoring. Certain gases, with low ignition temperatures, are easily combustible from minor sparks or overheating. Here, Exe fans, focusing on preventing ignition, might be more appropriate.
  • Vapour: Vapours emanating often from volatile liquids can be explosive when exposed to open flames or sparks. Depending on the liquid’s volatility, the choice of fan can differ.
  • Dust: Locations like grain silos or woodworking facilities present combustible dust threats. Combustible dusts don’t just pose ignition risks; their dispersion is a concern, too. In these scenarios, an Exd Explosion Proof Fan could be more suitable with its capability to contain internal blasts.
  1. Frequency of Risk: Considering how regularly an environment is exposed to potential explosions is vital.
  • Continuous: If risks are persistent, Exd fans, designed for maximum containment, may be crucial.
  • Intermittent: A combination of Exe and Exd fans might benefit most in fluctuating risk environments.
  • Rare: For infrequent risk settings, Exe fans, with their spark-resistant and preventive features, may suffice.
  1. Surrounding Equipment: Considering the neighbouring infrastructure is imperative.
  • Ignition Sources: Nearby machinery or systems can intensify the need for a robust Explosion Proof Fan if they are potential ignition sources.
  • Cooling and Ventilation Systems: An existing ventilation system can influence the fan choice. A potent ventilation setup could enhance the preventive capabilities of an Exe fan.

In many scenarios, there’s no singular answer. Both Exd and Exe fans bring unique strengths to the table. Situations might necessitate an integrated strategy, capitalising on the preventive strengths of Exe fans and the containment strengths of Exd fans. This holistic approach ensures a comprehensive safety net for regular operations and unforeseen challenges.

Choosing the Right Explosion Proof Fan

The science and technology driving an Explosion Proof Fan stems from extensive research, development, and field application. This commitment to design and efficacy is born from an overarching objective of ensuring unmatched safety in hazardous locales.

Exd fans, with their robust design, prioritise containment, ensuring that internal threats don’t evolve into larger external ones. They’re indispensable in places with regular explosive atmospheres.

On the other hand, Exe fans focus on a proactive approach, not just responding to threats but also preventing them from materialising. Their designs prioritise preventive methods, from top-notch insulation to well-optimised electrical connections, showcasing an evolved approach to safety.

Understanding these fans’ nuanced differences is crucial for industry experts. This understanding shapes equipment choices and ensures the workforce’s and infrastructure’s safety.

As industries evolve, the requirement for a trustworthy, efficient, and secure Explosion Proof Fan remains unwavering. Beyond operational efficiency, they symbolise a dedication to safeguarding assets and lives now and into the foreseeable future.

For more reliable HVAC products and solutions like an Explosion-Proof Fan, Spark-Resistant Fan, Exhaust Fan, and more, you can always trust JA Redden. We offer only the highest quality ventilation products from Sodeca Spain with ATEX certification. Visit our website at www.jaredden.com.sg

Explosion proof

Our assortment of ventilation products has been reinforced with a new series of inline mixed-flow fans in plastic casing Vents BOOST and Vents BOOST EC. The new product line is a logical follow-up to existing Vents ТТ PRO (EC) series.

Vents’ new product has embodied in itself all advantages of axial and centrifugal fans and received some serious additional improvements. One of its primary advantages is its high air flow efficiency reaching up to 5700 m3/h, which is almost three times more than models of ТТ PRO (EC) series can offer. Due to its high air flow capacity, Vents BOOST (EC) fans are an optimal solution for application in supply and exhaust ventilation systems of various commercial and industrial premises requiring powerful air flow.

These fans are made in polymer casing, which is perfect for premises with high humidity levels. The casing is reinforced with a metal housing adding it more reliability. Due to the conically-shaped polymer impeller with specially profiled blades, the air flow circular velocity is increased ensuring higher pressure and efficiency when compared with axial fans. Diffuser, impeller and airflow rectifier at the fan outlet provide smooth air flow distribution and enable the best combination of high air flow rate, increased pressure and low noise. Fan casing has external airtight terminal box for connection to power mains.

Vents BOOST fans are equipped with three-speed four-pole asynchronous motors and Vents BOOST EC line features energy-efficient ЕС motors. Fans are controlled by either a P3-5.0 three-stage or a smooth thyristor speed controllers, connected to the maximum speed terminal. EC models are regulated by a smooth 0-10 V controller.

The new fans are compatible with Ø 355 and 400 mm air ducts and may be installed in the beginning, in the middle or at the end of an air duct system. In order to achieve even greater air flow capacity, it is possible to install several fans in parallel. Moreover, it is also possible to install these fans in consecutive series with the purpose of increasing air pressure within the system.

For more product information, please our website at JA Redden.

There are various reasons why coils can fail prematurely. Sometimes, the coil was selected incorrectly, which made the coil significantly underperform. Most of the time, there is substantial corrosion or something else in the airstream that causes the coil to fail. However, most coils, when selected correctly with proper maintenance, can usually last from 10 to 20 years. Nevertheless, there are many factors that can affect the coil’s lifespan.

Reasons why coils fail prematurely:

  • 70% of all coil performance is performed by the finned area on a coil, while the rest will be from the coil’s tubes. The fin/tube bond, which is the most important manufacturing process of any coil, becomes less efficient with thermal expansion and contraction over time. This naturally weakens a coil’s life and it became less efficient over time after operating for some years.
  • During the routine cleaning of the coils, the dirt are often pushed into the center of the coil, especially on wet washing. This increases the air pressure drop across the coil. The cooling capacity of each coil is directly proportional to the amount of air going through the coil. If the air quantity going through each coil is reduced by 30%, it will mean that your coil capacity will also be reduced by 30%!
  • Cleaning agents also corrode the cooling fins and it is detrimental to the coil’s performance, since each area of the fin surface matters in the overall cooling capacity.
  • Coils usually fail because of leaks, due to erosion over time. The brazing on the coil construction will be failing from time to time, since the fluid travels through the coil at 0.6 to 1.5 m/s. Therefore, erosion is a major cause of coil failure, regardless of how well the coils are maintained.
  • Corrosive air in the environment can also be another cause of coil failure. As such, you need to have a reliable and experienced manufacturer for replacing coils in your HVAC equipments.

What does plant operators usually do?

There are so many factors that contribute to a coil’s life. It is not unusual for operators to choose the easiest way out to try to get the failed coil working again, due to the replacement cost of involved on a new coil or the downtime required to get the coil replaced. In the end, operators are probably spending numerous attempts to try to repair the coil, hoping that it will last as long as possible. Unfortunately, the attempts do not work well and the most likely outcome is that they will need a new coil anyway, so why waste the time and money on a temporary solution?

New Replacement Coil is the Best Solution!

The true fact that coils need to be replaced rather than repaired is mainly due to energy costs. If your coil is not performing to the desired levels, you will need to increase the energy to make it work at its peak performance. Energy increases might be slight at first, but they are guaranteed to continue to rise over time. Whatever adjustment you made to your system, it is going to reduce its energy efficiency and cost you money!

If you have ever experienced repairing a coil, then you know it is labour intensive and typically not a permanent solution. Instead of going through such non-productive attempts, JA Redden will be glad to provide you our Coil Replacement solution anytime.

Still Unsure With What We Can Offer You?