Table Of Contents
Noisy Air Duct Solutions
The sound of a noisy duct is not pleasant at all, especially if you are someone who loves their quiet sleep at night or peaceful daytime. Some vents are made of flexible materials that can sag or bend. Such materials are highly likely to bend when air blows through them.
The bends would, in turn, prevent efficient airflow, cause pressure build-up and thus a lot of unnecessary noise in your home. If this is the scenario in your house, or maybe your ducts are producing noise due to some other reasons, there is no better time to find a way to silence them.
This may seem like tiresome work; silencing the ducts? How? Well, there are various effortless ways to silence noisy vents. This article highlights some of the top ways to silence noisy ducts. Before we get to that, let us first look at some of the causes of noisy ducts.
What Are The Possible Causes Of Noisy Ducts?
Bent Flex Ducts
The bending of ducts could be caused by improper installation. When a duct is bent or sagging, it becomes difficult to allow airflow as required. The static pressure will therefore increase and subsequently generate some noise. This mostly happens with flexible ducts. Therefore, when you hire a professional to install your vents, you should be sure that they are well-versed in installing flexible ducts.
Air Pressure
When too much pressure builds up, it can also cause noisy sounds in the duct. Too much pressure build-up can also cause an expansion or contraction of the metal ducts. Now, when you switch on the system, the high pressure subjected to the air pushes against the sides of the metal, making it expand.
When this happens, you will likely hear a popping sound. Similarly, when the airflow slows down, the metal contracts back to its proper state. It will still produce a popping sound during the contraction.
Dirty Air Filters
Air filters are very critical parts of a duct. If your air filter is exposed to too much dirt or debris, it will highly likely be clogged with dirt, grime, or debris. Such clogs would prevent the adequate flow of air, thus causing noises. It is recommended that you ensure a regular inspection and cleaning of your air filters.
However, if an air filter is worn out beyond repair, you should consider a replacement. Similarly, it is not right to focus solely on the air filter. It is best to create a culture of regular inspection and maintenance of the entire ductwork. This is because a build-up of dirt, grime, or debris can prevent the proper functioning of various duct parts.
Closed Dampers
As we have highlighted above, a pressure build-up can cause some noise from the duct. Now, when your duct system’s dampers are closed, it offers higher chances for pressure build-up and subsequently produces unnecessary noise.
This is most likely to happen when you close several dampers; closing a single damper is less likely to cause pressure build-up. It is also important to note that closing several supply vents may cause ductwork malfunctioning.
How To Silence Noisy Ducts
Noisy ducts can cause you a lot of disturbance at home. However, there are various practical solutions to silencing noisy vents in the house. This section provides you with multiple options to try when you have noisy ducts in your house.
Install a Bypass Duct
In a multi-zone duct system, installing a bypass could help with pressure regulation. However, before settling on this option and installing a bypass duct, it would help to consult a professional to see if it is best to install a bypass duct. Generally, installing a bypass duct is a perk when one seeks to minimise the risks of preventable problems and eliminate unnecessary system strain.
However, installing a bypass duct where none is required may also cause more harm than good. Therefore, even though a bypass duct would help curb the problem of noisy vents, it is best to seek an expert’s advice on whether it is right to install one or not.
Adjust the Fan Speed
During the installation of a ductwork system, it is necessary to contemplate the amount of airflow. Most experts are well aware of this fact, and it is unlikely to find a professional setting the fan speed too high during the installation. However, if the labour you had hired to install your system had set the fan speed too high, it would be good to lower the fan speed.
Dropping the fan speed would help reduce the static pressure, which minimises the probability of duct noises. However, it is essential to be very keen when lowering the fan speed. It is recommended that you conduct due diligence to ascertain the proper level of airflow required. Reducing the fan speed to the wrong level may prevent the airflow to other areas as needed.
Replace with a Bigger Duct
Sometimes the problem lies in the ducts that you had installed. Vents come in various sizes. It could be that the remaining part of the entire duct system is in good working condition; however, the ducts that you had installed are too small to shelter the volume of air required for the smooth operation of the ductwork system.
If this is the scenario, you can either consider installing several small ducts or replacing them with larger ducts. Similarly, you can install grilles or high-velocity registers. These can also minimise the ducts noise by enhancing efficient airflow. Additionally, you can consider installing more significant return and supply plenums to reduce the amount of noise coming from the air vent.
Inspect the Air Register on the Return Vent
Noise from the duct could also be caused by clogging in the air register on the return vent. At least every HVAC system has an air register that facilitates the entry and removal of air from the ductwork with the help of vent covers. If dirt, grime, or debris block the air register on the return vent, there is a high probability that pressure will build up in the duct, thus causing a lot of unnecessary noises.
To prevent this problem, you will need to inspect the air register to see if anything is blocking it. Should there be some dirt particles or debris, ensure that you remove them before restarting your ductwork. However, if you witness no change even after removing the matter blocking the air register, you could try installing some more return vents.
Having more return vents would mean that a lot of air is vented out of the ductwork. With a lot of air vented out of the ductwork, the pressure inside the duct would reduce, which would, in turn, reduce noise coming from the duct.
Separate the Duct from the Framing
Sometimes, the ducts rub against the framing, causing a lot of noise. This rubbing may be caused by a person walking on the floor above the ductwork system. Similarly, when cold or warm air travels through the ductwork, the duct may rub against the framing. How can you prevent the noise produced by the duct from rubbing against the framing?
It is pretty effortless. All you need is some rubber pads from a nearby hardware store. Once you purchase the rubber pads, you need to fix them between the duct and the framing. With the rubber pads installed adequately between the frame and the duct, you will not hear any sounds from the vent, even when the duct rubs against the framing.
Conduct a Duct Blaster Test
The duct blaster test comprises a small fan and a pressure gauge. The process involves subjecting the duct system to pressure to evaluate the ducts’ air leakages. It is advised that you perform this test for your duct system once in a while to check for damages such as wrongly placed seals or cracks. If you find none of these, it would mean that your ductwork is in good working condition. You can perform this test by yourself without calling for professional help.
Seal the Ducts Properly
This is another vital component in the maintenance of a duct system. In most cases, people do not realise when their ducts are leaking. However, if you are keen enough, you would hear some roaring, whistling, hissing, or clicking sounds coming from your vent. Such sounds are a sign that your vent is leaking.
Therefore, you should make it your custom to check the air duct system regularly for any leaks. Start by running the system to inspect the accessible joints for leaks. Should you notice any leaks, ensure that you seal them using foil-backed tape, mastic, etc. It is better to use mastic or foil-backed tape since other sealing tapes wear out after some time.
Similarly, it would help to seal behind the grilles and register since the duct touches the wall along these areas. After doing the above procedures, keep a regular inspection of the ducts for your air conditioners or ventilation system to prevent any future leaks.
Clean the Ducts Regularly
Yes, cleaning the ducts is a good move towards maintaining your ducts to prevent them from producing noise. Regular cleaning will ensure that you remove the dirt or debris that may block the register or air filter.
Similarly, as you clean, you will identify the parts that need replacements. It would also help to replace the air conditioning filters at least every two to three months. This would prevent dust accumulation that would interfere with efficient airflow.
Consider Insulating the Ducts
You can regulate how the ducts take air in or out of your home by insulating them. It would also help to insulate the basement walls so that both the basement walls and the ducts are well insulated. However, it is best to protect the attic since insulating the basement walls will produce warmth in summer and cold in winter. That may not be a good experience entirely.
No Change? Hire A Professional
We hope that the above solutions provided in this article help you curb the problem of noisy ducts in your house. While these solutions are generally effective, it is also possible that the problem may refuse to go away even after you have tried everything. If that is the case, you should not hesitate to call a professional to check the entire duct system and find the problem.
Professionals are equipped with the proper skills and tools to handle your duct system. With the appropriate inspection, they will identify the issues within the ductwork and offer solutions.
