An inline fan is a type of ducted fan used in an HVAC system to push or pull air through a ventilation or cooling system. They are generally connected to a vent or grille in order to draw air into the system when it is being used for ventilation. In the case of cooling systems, they use electricity and work by compressing and expanding air. Such fans are widely used in commercial buildings and houses. it has a lot of advantages but at the same time, there are some problems that may be caused by the inline fan.
Have you ever noticed the annoying hum of an inline fan? This is a problem that many people experience, especially if they are trying to sleep. Fortunately, there are several ways to soundproof your inline fan and reduce noise so it doesn’t bother you or anyone else in your home. Keep reading for some helpful tips on how to get rid of that pesky hum!
The Causes of Inline Fan Noise
Inline fans are great in use but it is not a secret that they can be too noisy. The level of its noise depends on different factors such as type of fan, length of ducts, location, and so on.
Stat with using a dB meter to measure the noise level of a working inline fan. If it’s more than 75 dB you must start looking for problems in your inline fan system. They can be caused by non-proper installment or something may be wrong with part or all of your unit – it might need repairs or maintenance if it makes unusual sounds when it runs. Let’s check the common causes of your inline fan noise.
Inline Fan Speed Problem
The inline fan speed is one of the most common causes of noise. If it’s not set right, you may experience humming or rattling sounds coming from your air ducts because parts are vibrating against each other to produce that annoying sound.
Another case – if the motor turns faster than what it should be then probably you’re hearing a noise from your inline fan. You can try to change its speed or add a small piece of rubber between the blades and motor housing – it should be enough for reducing this kind of unpleasant humming sound.
Vortex Shedding of Inline Fan
It means that your fan is not balanced and it starts to vibrate at high rpm. It can also produce a loud noise or even cause damage to the whole unit. You must have this problem fixed immediately.
If you’re trying to fix the problem yourself, first check all screws holding blades together as well as those which keep them in place on the motor housing. Tighten everything if needed but do it carefully so you don’t break some parts of your inline fan system while doing this kind of repair work. Another thing that might be done by anyone is changing airflow direction from one side to another (it should be changed every time when correct balancing is done).
Inline Fan Load Problem
The inline fan load is another common cause of the noise. It occurs when the air pressure in your ventilation system is too high and it can be caused by wrong duct design, improper placement, or size of inline fans – especially if there is more than one unit working together on a single system. There’s nothing that you could do about this problem yourself so don’t waste your time with DIY tips! Always call professionals to solve such issues because they have special equipment for checking airflow, designing proper ducts, and installing everything correctly.
Inline Fan Structure Vibration
If the inline fan is not mounted properly it may start to vibrate and produce noise. This problem could be easily solved by balancing your unit or using rubber pads between parts that might cause an unpleasant humming sound in the working process. If nothing helps then you must check how strong and steady all screws and bolts holding different components together are, especially if they’re made of metal – such areas should never contact each other so use this trick for avoiding noisy fans. Don’t forget about proper installation when buying any kind of device for ventilation systems because structure vibration can also appear in case if there’s not enough space allowed inside ducts or around inline fans (make sure everything has its own place). Also, don’t hesitate to ask professionals what else can be done in case you’re not sure about something.
How to Soundproof Inline Fan?
If you want to soundproof your inline fan you can try the following tips. Let’s check them one by one.
Use the Cardboard to Isolate the Inline Fan.
You can use thick cardboard for soundproofing your inline fan. It’s cheap and easy to cut, you just need large pieces of corrugated board that will fit inside the ventilation system (you may also cover the whole unit with it). Make sure there are no gaps between sheets – they should be attached firmly around metal parts by using duct tape or stapling them together.
It helps reducing noise in case if you put several layers of cardboards above the blades so vibrations have more places to go away from this area instead of staying in one place where they could cause unpleasant humming sounds when working properly. If possible, fill all other available spaces between parts and covers with these boards as well because the insulation is very important here. You won’t regret buying such a cheap tool to eliminate the noise.
Use Inline Fan Insulating Ducts
Inline fan insulating ducts are another cheap and easy-to-use solution for soundproofing your ventilation system. These special covers are made of thick plastic or metal with small holes in the surface and a cable running along their length. When using such an item, make sure there’s no gap between its end part and any other component that makes noise during operation. If needed cover everything with several layers of cardboard but only on one side so you can attach this tool easily without creating additional gaps inside vents.
This device allows reducing airflow noise because hot air will touch outer walls instead of moving through internal components of the inline fan – this will reduce vibration and eliminate possible humming sounds. As well as any other insulation material, in-ducting sound proofers also help with condensation problems because they’re able to keep strong airflow coming out from ventilation units away from cold surfaces that may cause water vapor freezing inside ducts.
Buy a Fan Speed Controller
The fan speed controller is a speed controller that allows changing the device’s rotational speed by adjusting voltage up or down. If you have an older ventilation system with one big motor, this could be exactly what you need to reduce noise because it can help to slow down blades rotating and make them less noisy.
Use Neoprene Duct Clamps to Join the Fan and Filter or Silencer
Neoprene duct clamps are another type of insulation that can be used to reduce inline fan noise by attaching the components together. They’re able to hold several parts tightly so there’ll be no gaps between them and vibration won’t escape through these cracks.
Inline fans might cause a lot of issues because they usually have big blades which turn really fast when working properly – this process is relatively loud unless you add some other elements like reducing paddles or turning down voltage, but sometimes even this may not help if your unit doesn’t perform well enough (the usual problem with cheap models). A clamp could solve all problems in most cases because it reduces airflow turbulence along its length and makes vibrations travel away from critical areas where noises seem louder than usual.
Use Muffler or Silencer
Using a special muffler/silencer box will help to reduce noise in most cases. It’s usually made of thick metal and has multiple layers of insulation inside so the hot airflow won’t touch outer walls during its travel. The silencers are relatively cheap because they’re just containers with some kind of foam or rubber used for sound absorption purposes – it reduces any unwanted whistling sounds caused by high-speed air movement through vents. You should avoid buying plastic models since they don’t work well enough when creating strong pressure inside ventilation systems (they’ll be torn apart after several months). Just make sure there is no gap between muffler ends and other parts where turbulence could be created.
Use an Acoustic Enclosure for Inline Fan
If you’re looking for the most effective solution to reduce inline fan noise, consider buying an acoustic enclosure because it’s made especially for particular ventilation units. The acoustic case is usually attached directly to your unit but may also be used as a part of a silent box with thick foam inside or a muffler/silencer box. It has several holes on its surface and internal panels covered with soundproofing layers designed to absorb any airflow turbulence created during operation. All these features help prevent vibration from leaving the device via vents so there will be no whistling sounds at high speeds. Additionally, every acoustic enclosure comes pre-drilled which allows easy installation without creating additional gaps between parts where noise could escape.
Acoustic enclosure is usually really expensive because you need multiple thick insulation layers which are very costly to manufacture. On the other hand, if your budget allows this type of soundproofing work done properly, there won’t be any whistling sounds or humming noises – just strong airflow that will leave the ventilation unit silently.
Invest in a Quiet Inline Fan
If you want to get rid of all problems with noise, consider investing in a quiet inline fan because it’s specifically designed for low-noise operation. It has special blades that are rounded at the end and rotate slowly when working properly like propeller blades. The slow rotation speed reduces air turbulence inside ventilation systems which means there will be no whistling or humming noises even if your internals aren’t very good quality. Additionally, using an insulated box made from thick layers of insulation materials can help reduce any airflow escaping through ducts so sounds won’t enter living spaces.
However, every model comes with its own power use ratio – usually, they need more energy to create strong pressure but don’t have powerful motors compared to standard fans found on inline fans. Therefore, if you don’t mind spending a bit more for energy and noise reduction purposes, consider buying an expensive quiet model to get rid of all problems with sounds in your house or office – they’re worth every penny! Or you can do something on your own watching DIY advice on Youtube and other sources: