What is louvers in HVAC

In my last article, I wrote about CFM in HVAC: a device used to calculate the rate at which air flows through an HVAC system. Truly, an HVAC system with a high CFM can cover a lot of space; but the efficiency matters a lot in HVAC. The best way to achieve high efficiency is by regulating the rate by which your heating and cooling system work, and that is why manufacturers designed oeuvres specifically for that purpose.

I am neither a psychologist nor a mentalist, but I am positive that right now you are wondering “what are louvers in HVAC?”. Well, in the past, I have delighted my readers with my fact-finding research and I don’t intend to disappoint them in this article, so read till the end to find out all you need to know about louvers.

What are HVAC Louvers

Louvers in HVAC also known as Louvre is an assemble of well-arranged equally equidistant vertical blades, wood, slips of glass, wood, laths, sliths, and some other materials that help regulate the flow of air and also serve as a pathway for light into the building.

It is a ventilating device that brings in fresh air from the outside, and also simultaneously filters the air, to rid it of harmful substances like dirt and debris so that the quality of air in circulation can be improved.

How do HVAC louvers work

Louvers serve as the entry and exit point of your ductwork because it covers the openings where your HVAC system takes in and exhausts air.

To take in air, louvers make use of the inbuilt fan to draw air into the HVAC system. This air then passes through the louvers’ blades. The blade takes in air and prevents unwanted elements like; water, sand, and from getting into the ductwork so that the whole system will not be corrupted. To repel unwanted substances, the fan pushes the air out through the louvers back into the atmosphere.

HVAC louvers free area calculations

You can get the free area of your HVAC louvers by dividing the total open area of the louver (provided that you have subtracted likely obstructions like; blades and frame) by the total wall opening. However, you should know that Louvers, regardless of the size usually with a standard free area.

The factory standard for a louver comparison is 48″ wide by 48″ high. Nonetheless, free area differs on some criteria like sizes, models, and options ( configuration, reflection, and accessories). Each of these criteria affects the free area in one way or the other, and as such must be considered before choosing the best louver that will suit your need.

Is the HVAC louver safe

Yes, it is safe to use HVAC louvers. I said, “yes” because I’m assuming you used the word “safe” to ask if it is ok to use Louvers and that will be the basis on which my analysis herein.

Louvers filter the air coming through the ductwork into the building and also help to regulate the rate at which air is being distributed within the premises. Apart from that, they also protect against hurricanes, rainfall, and direct sunlight; therefore, just as you have rightly said, it is safe to use louvers for your HVAC.

HVAC louvers size chart

HVAC louvers size chart is a table showing a series of estimated standard sizes for different shapes of an HVAC louver ductwork. HVAC ductwork can be a round metal pipe, flexible, or rectangular shaped. In each table is listed, duct sizes with a corresponding design airflow. A typical HVAC louver should look like this:

Flexible duct

Duct Size Design Airflow

5″ 50

6″ 75

7″ 110

8″ 160

9″ 225

10″ 300

12″ 480

14″ 700

16″ 100

18″ 1300

20″ 1700

Types of Louvers in HVAC

We have 4 major types of louvers in HVAC: we have, stationary, combination, adjustable, and air measuring louvers.

Stationary louvers

A stationary louver usually has an angular or airfoil patterned blade that helps protect against adverse weather and depletion of sound.

Adjustable louvers

They are also equipped with airfoil blades and one of the most common types of Louvers.

Combination Louvers

This type of louvers has blades that are based on the level of static pressure. The more the total static pressure shuffles between stages, the wider the fan opens. Some combination louvers have a backdraft damper blade and it is completely from aluminum to proceed against corrosion.

All measuring reassuring louvers

This type is equipped with vertical blades with slightly opened space to prevent water from getting into the device.

Drainable HVAC louvers

Drainable HVAC louvers have an inbuilt gutter that serves as a temporary storage house for water, moisture, dirt, and debris extracted from the airstream before it is finally transferred to outside the building.

After collecting the unwanted particles, they will be redirected to another channel called louvers jamb which then drains the particles through the louver sill. Drainage HVAC lovers are very effective, hence, they are the most ideal for places with medium or high air velocity intake.

Fresh air intake louvers

This type of louvers is used majorly for taking in fresh air from the outside into the building. It has fixed blades that are carefully arranged in a way that will accommodate the passage of air through it while also preventing water or moisture from getting in at a supposed inlet speed. Fresh intake louvers are designed with a synthetic filter and an optional damper located at the back of the louvers.

Some qualities of Fresh intake louvers

1. They are made of extruded aluminum which makes them both durable and corrosion-resistant.
2. Its blades are attached to the central frame with screws.
3. They are designed to be 100% water-resistant and the blades are inclined to an angle of 45° to prevent rainwater from penetrating the building.
4. You can have multiple sections assembled if you desire for it.

Custom HVAC louvers

Just like the name implies, custom HVAC louvers are customized louvers designed to match specifications. Unlike the fresh intake and drainable louvers which are readily available, custom louvers are not. The structure of the fan and every other necessary material will be assembled based on the user’s description.

What are louvers vent

Louver vents are physical installations that bring in fresh air through fixtures that vertical pieces to naturally regulate the heating and cooling systems.

This kind of ventilation is meant for both interior (rooms and offices) and exterior (vehicles) uses. Before the introduction of technology, louver vents were made majorly from wooden slats that let in natural air and sunlight, while keeping out moisture at the same time. But with the advent of technology cones improve: nowadays, louver vents are mainly made out of metal with smaller specific rows of vertical slats that control air distribution.

What is the louver in the air conditioner

This kind of louvers is adjustable assemblies of slats designed for room air conditioners. Each louver arrangement comes in box-like cases within which sets of horizontal and vertical louvers are placed.

Every single vertical and horizontal louvers in the set are connected so that they can move uniformly. The case comes with an actuator wheel attached to it. This actuator wheel is usually connected to one of the upstream louvers so that once the actuator rotates, the louvers will rotate as well.

A minimum of one, from the sets of louvers, must be positioned too close to forcefully push out air from the other opened louvers of the ac unit.

What is the difference between a damper and a louver

Damper and Louvers have some similarities because they both use horizontal blades, exterior frames, and wall placement; however, despite these obvious similarities, each component plays different roles which are vital to the operation of the entire system. The key difference between these two components is their blades.

Louvers’ blades are constant; and as a result, they cannot move and do not have complete control to regulate the airflow. On the other hand, dampers boast more flexible blades that rotate and as a result, can regulate the flow of air.

However, the two are best used together because: for instance, in a situation whereby there is the need to control the flow of air and fluids synchronously. This is because each component is designed to handle different temperatures and substances. While the louvers will protect the system against water infiltration, the damper will shut off the air when needed.

If you want to learn how do dampers work in hvac, please refer to our previous dampers HVAC guide for more info.

Do louvers worth buying

Yes, louvers are a worthwhile investment, and here are a few reasons why you should have them installed.

1. It supplies the HVAC system with fresh air thereby improving the overall functionality of the system and the general quality of air in circulation.
2. Louvers are made majorly with aluminum, as a result, they provide your building with some privacy and security.
3. Louvers also allow homeowners and building managers to regulate the amount of natural light getting into the indoor spaces from outside.