HVAC Duct Fittings, Sheet Metal Duct Fittings Supplier

HVAC Duct Fittings: The Ultimate FAQ Guide

What are the Standard Duct Sizes?

Most standard duct sizes for rectangular ducts range from 35*40 inches to 3 *7 inches depending on the airflow requirements per cubic foot.

Diameter for round ducts ranges from 4.9 inches to around 41 inches.

It also depends on the airflow requirements per cubic foot.

What is an AC Duct?

AC ducts are conduits that deliver and remove air from a room ensuring proper air conditioning.

Why you need HVAC Ductwork Transitions?

HVAC ductwork transition assists in changing the shape of your ductwork.

For instance, changing your ductwork from a rectangular shape to a round shape.

Ductwork transition

You can also use it when changing the size of the ductwork from one with a large diameter to one with a smaller diameter.

What is the Difference Between duct transition and duct boot?

Duct transition in ductwork helps in changing the shape or size of the ductwork.

For instance, if you are changing from a rectangular duct to round ductwork.

Duct boot vs. duct transition

On the other hand, a duct boot is used to change the direction of your ductwork.

Apart from T Duct Transition, Does Biyang have Other Designs?

Yes, Biyang has other designs of duct transitions that depend on the design of your ductwork.

How Do You Convert Round Duct to a Rectangular Duct?

First, determine the diameter of the round duct by using a tape measurement preferably In inch.

Then, divide this measurement by half to obtain the radius of your round duct.

Next, get the square of your radius. For instance, if your radius is 4 inches, its square is 16.

Multiply the answer with pi (3.14). This is the area of your round duct in square inches.

Choose a rectangular duct with the same area as that of your round duct.

You can do this by getting the product of two adjacent sides of a rectangular duct.

Purchase an adapter that will help in converting the round and square ductwork.

Duct adaptor

Is there a Difference between a Circular Duct and Pipe?

The material used in the manufacture of pipes is a long rectangular sheet which is flat and welded into a round shape that is open-ended.

Insulated circular duct

Circular ducts utilize insulated galvanized steel.

Manufacturing of pipes takes into consideration the transportation of gases or liquid at a standard flow rate and temperature.

Fabrication of circular ducts takes into consideration the flow of fluid at varying temperature, pressure, and flow rate.

Circular ducts can have different cross-sections which lack in pipes.

How Do You Use Duct Clamp?

Duct clamp

First, expand the duct clamp by turning the screw in an anti-clockwise direction.

This makes it large enough to allow it to slide over the duct.

Second slide the duct clamp over the duct.

Next, insert the duct over your preferred fittings that it attaches to.

Then slide the duct clamp across the joint in between the duct and the fitting.

Tighten the duct clamp using the screw in a clockwise direction.

It contracts the duct clamp encircling it on the duct till you achieve the tightness you desire.

What is the Best Hose Clamp for Spiral Duct?

The best hose clamp for spiral duct is the spiral clamp whose design helps in minimizing damages to the duct during fastening.

The high-temperature-resistant rubber inside ensures the connection is leaking free.

Hose clamp

How Do You Calculate CFM of a Duct?

• Calculate the velocity pressure inside the duct using a pilot tube assembly to find the velocity flow in feet per minute. Connect this pilot tube assembly to a pressure sensor.
• The cross-sectional area of the duct depends on the type of duct you have, that is, circular duct, square or rectangular duct. For the square or rectangular duct, use the equation A= X*Y where A is the cross-sectional area, X is the duct height, and Y is the duct width in feet. For round duct, use the equation π x r² where A is the cross-sectional area, π is 3.1459 and r is the radius in feet
• Find the cross-sectional area of the duct.
• Multiply the cross-sectional area of the duct and the velocity flow to get the CFM.

What is a Duct Connector?

A duct connector is a  joint with some flexibility that is airtight.

It is made out of stainless steel or galvanized steel which is suitable to fit between flexible ducts.

Duct connector

What is a Fire-rated Flexible Duct Connector?

A fire rated flexible duct connector is a duct connector that can withstand combustion over a specific duration.

They can either be of one of three classes, class 125 fire rated flexible duct connectors, class 150 fire rated flexible duct connectors, and class 360 fire rated flexible duct connectors.

How Do You Install a Flexible Duct Connector?

When installing a flexible duct connector, avoid twisting the flexible duct connector since it won’t function properly.

Aluminum flexible duct

Also, prevent wrenching on the hose during the installation process.

Only use wrenches on the hex section of the flexible duct connector fitting.

Prevent over bending of the flexible duct connector.

Ensure that the radius of the installed flexible duct connector is more significant than the minimum radius bend.

Lastly, don’t abuse the flexible duct connector, including mixing these connectors with other tools and components during the installation process.

Any mishandling of the flexible duct connectors results in their failure during the operational period.

Use a proper length of the hose and appropriate end fitting.

What is the Advantage of the Flexible Duct Connector?

Flexible duct connector

• A cheaper option than metal duct connector
• Easier to install
• They are flexible, allowing for bending in tricky places.
• Low labor cost

Where Can You Use Duct Boot?

Duct boots are useful in changing the direction, shape, and size of your ductwork like replacing your ductwork from rectangular to round or square to round.

How Do You Install Duct Register Boot?

• First, use an appropriate cutting tool such as a duct cutter.
• Cut the register boot to the appropriate length.
• Next, join the register duct boot into the ductwork, ensuring that it fits perfectly well.
• Lastly, use the screw to hold the register duct boot firmly in place tightly.

How Do You Check Ductwork for Leaks?

Look for the obvious tears on your ductwork.

Tears are a sign that there are leaks on your ductwork.

Seal any tears you find using an appropriate sealant.

The other option is to switch on full blast your ductwork.

It is easier to locate leaks when your ductwork is blowing than when it is silent.

The higher the amount of air blowing, the greater the chances of you finding available leaks.

You can also check for leaks on the duct joint.

These are the points where two ducts meet.

If you feel any air oozing out by placing your hand around here, then there is a leakage.

Also, check on areas where there are duct tapes.

These tapes become worn out with time, thereby exposing the leaks.

Remove such tapes and replace with new ones.

Seal these areas appropriately to avoid leaking. You can also use a smoke pencil or an incense.

What is the Function of Duct Splitter Damper?

Duct splitter damper directs a certain quantity of air into a given duct.

However, most manufacturers don’t recommend its use since it increases static loss leading to the creation of turbulence.

Splitter duct

A better option to a duct splitter damper is the volume control damper.

3-way Duct Splitter and 4-way Duct Splitter, How Do They Compare?

Both of these duct splitters are vital in directing the airflow during the ventilation of your room.

The main difference between these two-duct splitters is the number of minor ducts each consists that facilitates airflow.

3-way duct splitter splits the main duct into three minor ducts which direct the flow of air into three different directions.

On the other hand, a 4-way duct splitter splits the main duct into four minor ducts that direct airflow into four different directions.

Which types of HVAC duct fittings do Biyang offer?

Biyang offers a wide range of HVAC duct fittings to suit your needs.

These include; celling boxes, pant wyes, square to round transitions, Tee wyes, 45 degree, and 90 degrees elbows and much more.

We customize these duct fittings to fit your ductwork requirements.

How does HVAC System Work?

First, sucking of the warm air from the room takes place through a grille which is on the base part of the machine.

The warm air flows over chiller pipes via which there is a coolant circulating.

This helps in cooling the warm air and removing excess moisture present.

After this, the cool air flows across a heating element.

Depending on the season and the temperature, this part can be turned on to warm the air as it flows over it.

There is a fan at the top of the system that forces the air into another grille.

In case you switch off the heating element, the air flowing into the room will be somehow cold, which cools the place gradually.

In the meantime, a coolant flows via the chiller pipes picking heat that is coming from the air blowing over the pipes.

This causes the refrigerant to evaporate, resulting in a hotter gas.

It is this hot gas that flows from inside the room to the outside into a compressor that is outside the building.

Here, various metal plates distribute this heat to the atmosphere.

There is an electric fan that facilitates the process of pumping out this air.

Gradually, there will be a change in the temperature of the building.

Is Round Ductwork Better than Rectangular?

Round duct vs. rectangular duct

Round ductwork is ideal for directing the air that has a low-pressure drop.

It also produces less noise, which can be a nuisance to the occupants of the room.

Lastly, its installation cost is far less than that of rectangular ductwork.

What is a Normal Static Pressure in the Ductwork?

Normal static pressure in ductwork is the maximum resistance pressure that the HVAC fan has to blow.

That is when there is maximum resistance within the ductwork such as in no airflow condition.

Static pressure results in the application of more force while delivering little air circulation.

Static pressure differs depending on the size of your ductwork.

How Do You Increase Airflow in Air Ducts?

You can increase the airflow in air ducts by sealing any leaks available in your ductwork.

Leaks reduce the amount of air flowing through your ductwork and in return, increases your energy bills.

You can also increase the airflow by cleaning the duct filters.

Dirt accumulating o the duct filter reduces the amount of airflow since there is no passage for the air.

If the duct filters have become old, you can consider replacing them for efficient working.

The third option of increasing the airflow in your duct is by using the correct ductwork when designing.

Selecting an inappropriate size leads can cause inadequate air supply, which in turn increases your energy bills.

CFM vs. Static Pressure, What is the Difference?

CFM is the measure of airflow between two points within a duct due to the differential pressure between these points.

The static pressure of the other hand refers to potential energy measurement of air unit at a given cross-sectional point of a duct.

What Material is Duct Insulation Sleeve?

The best material for use in duct insulation sleeve is fiberglass material.

Fiberglass is available in different R-values and thickness.

Duct insulation sleeve

Other materials available for use in duct insulation sleeve include mineral wool, cellulose, natural fibers, polystyrene, and polyurethane.

Each of these materials has its advantages and limitations for use.

What is the Function of the Insulation Sleeve?

Insulation sleeve help in reducing the amount of heat lost within the ductwork as air flows.

Heat loss within the ductwork results in uneven temperature within your room.

R8 Duct Insulation Sleeve vs. R6 Duct Insulation Sleeve; What is the Difference?

R8 duct insulation sleeve is thicker than that of R6 duct insulation sleeve.

Thus R8 duct insulation sleeve offers better insulation than R6 insulation sleeve.

Duct insulation sleeve

R6 duct insulation sleeve is less efficient when it comes to heat insulation than R8 duct insulation sleeve.

R8 duct insulation sleeve costs more than R6 duct insulation sleeve.

The exterior diameter of the R6 duct insulation sleeve is smaller and much flexible; thus It offers better thermal efficiency than using R8 duct insulation sleeve.

How Do You Install Insulation in Heating Ducts?

You will need a foil-faced with fiberglass insulation rated with a higher R-value like R-6. Select a metallic foil tape as recommended by your insulation manufacturer for sealing and holding the insulation in its place.

Clean the foil surface that you want to insulate before application of the tape.

Remove the paper off the tape while applying it on the surface to prevent sticking of the tape on itself.

You can apply it on top of the old insulation or if it is completely worn out, consider replacing it.

Using a knife, cut the insulation to the width required for it to fit correctly around the duct.

Check to ensure that the duct is insulated correctly.

Does Biyang have Rectangular Ductwork Fittings?

Yes, Biyang offers rectangular duct fitting of different sizes that meets the demands of our various clients.

Why Do You Need a Flexible Duct Connector?

Flexible duct connector plays a vital role in isolating the noise and vibration throughout the system as the blower or fan operates.

This results in smooth ventilation for smooth air conditioning.

Are There Standard Rectangular Duct Sizes?

Yes, there are standard rectangular duct sizes that can fit in different ductworks.

These rectangular duct sizes are compatible with different types of ductworks.

Rectangular Duct

How Can You Measure HVAC Duct Fitting Dimensions?

Measuring HVAC duct fitting dimensions depends on the type of HVAC duct.

For Rectangular HVAC, start with measuring the top width of your HVAC ductwork.

Using the tape measure, extend the measurement to the opposite side, and record the measurements.

Measure the height of the HVAC ductwork using a tape measure.

Take the width and height as the actual fitting dimension of the rectangular HVAC ductwork.

For round HVAC ductwork, using a string, wrap it around the circumference of your HVAC ductwork.

Note the starting point and where the string meets the starting point.

Remove the string and place it against a tape measurement to find the length between the two points.

This is the circumference of your ductwork.

Calculate the diameter by dividing the circumference by pi (3.14).

What Does the Equivalent Length of a Duct Fitting Mean?

The equivalent length of a duct fitting is the length of a straight duct that imposes the equivalent resistance to the flow of air as a specific fitting.

This length is vital for ensuring the proper flow of air distribution along the duct.

What is HVAC?

HVAC stands for Heating, Ventilation, and air conditioning.

It refers to a technology of ensuring proper indoor and vehicular ventilation and thermal comfort.

What is the Best Material for Ductwork Fittings?

The best material for ductwork fitting is galvanized steel or stainless steel due to the various advantages it offers.

For instance, it does not rust, thereby giving it a longer period.

They also offer strength and rigidity, which means it will cost less in maintenance as well as the toughness your ductwork needs.

What is the Duct Insulation Protection Shield Used For?

Duct insulation protection shield function to protect the ductwork insulation.

They also evenly distribute the weight of the ductwork at each hanger.

Which Types of Ventilation Duct Systems do Biyang Offer?

Biyang offers a wide range of ventilation duct system, including exhaust ventilation, supply balanced ventilation duct system, and energy recovery system.

Also, we offer customized ventilation duct system as per customers’ requirements.

Can Biyang Custom HVAC Duct Fittings?

Yes, we can customize HVAC duct fittings as per the client’s requirements.

You have to submit the measurements and design of your HVAC duct fitting.

How to Decide the Duct Fittings for Your HVAC System?

When deciding the duct fittings for your HVAC system, you need to consider several factors.

For instance, you need to consider the size of your HVAC system.

This will help you select the appropriate size of a duct fitting that you want for your HVAC system.

Also, consider the size of your blower or fan. A proper duct fitting should not interfere with the working of the blower or fan.

You also need to consider your HVAC system material.

There are different materials for the HVAC system, and as such, you need a fitting that is compatible with the material of your HVAC.

Your duct fitting should consider the design of your HVAC system for it to fit into the system.

Can Duct Fittings be Custom Made?

Yes, duct fitting can be customized depending on the client’s requirements.

All you have to do is submit the design to your manufacturer, and they will handle it for you.

What is the Lead Time for Custom Fittings?

The normal lead time for custom fitting is between 7-10 days

Can Biyang Provide Drawings for the Custom Items?

Yes, Biyang provides drawing for custom items with a lead time of between 2-3 days.

Can Biyang Accept the Goods Consolidations with Other Suppliers?

Yes, Biyang accepts goods consolidations with other suppliers.

What is the Lead Time for the Bulk Order for Fittings?

The lead time for a bulk order for fittings is around 30 days.

Can Biyang Provide Samples for Fittings?

Yes, Biyang offers standard samples for fittings free of charge.

How to Maintain the Quality for Fittings?

Biyang has an inline QC for each step of production.

What is the Advantage of Biyang Fittings?

Biyang duct fittings cover almost all standard categories, including custom-designing the fittings as per your design.

How to Ensure the Steel Material Thickness?

Biyang strictly follows the customer’s steel thickness requirement.

We usually use one grade up for steel thickness issue as most steel thickness is negative tolerance in China.

Does Biyang have the Report for the metal Duct Fittings Material?

Yes, we will provide you the mill test report.

What Certifications does Biyang have for Ventilation Duct System?

We have ISO 9001 certification, CE, SGS fire rating report as well as ROHS certification.