10 Apr. 19

Why is my heater so loud?


There is no feeling that beats being snuggled up in bed in a perfectly heated room. You could even make yourself a cup of tea, put on your favourite TV show, and enjoy. It is unarguably true that the best way to enjoy winter is to have your home temperature perfectly warm. Although some people prefer using a traditional fireplace to keep their house warm, others cannot afford the expense that comes with doing that, so they purchase an electric heater.

As a result of the traditional noise made by furnaces, they are ordinarily placed in a different room. This way, their noises will be far from places that constantly require quiet in the house. However, if you place your furnace somewhere close to the rooms that you regularly make use of, the noise may, over time, become unbearable. This noise can be excessive, and in cases like this, it is often because there is a malfunction.

Loud heaters are irritating

Excessive loud noises from your heater can be annoying, so much so that your furnace starts to displease you. This noise is often so loud, that even if you wanted to ignore it, the intensity would not allow you to. More often than not, the noise creates a banging and whistling sound. The sound may be resulting from a dirty air filter. Your air filter could have been clogged by dirt thereby making it hard for air to pass through conveniently.

It could be as a result of the ductwork of your furnace which could be lacking proper lubrication. If you, however, own an old heater, it could be that the motor needs to be repaired or even changed as a whole.

While all these, may sound scary, do not let it scare you. A furnace, like every other HVAC system, is not exempted from getting faulty at one point or the other. The good thing about these HVAC systems is that, once you quickly detect the problems, you can put them to bed without allowing them to dive into more significant complications.

To solve the problem of your heater making so much noise, we have decided to provide you with some hands-on “Do it yourself” methods which, if applied carefully, should solve the problem.

Before delving into the crux of how to fix your noisy furnace, it is vital to have a grasp of how your heater works. Sequel to that, you have to understand the causes of these noises because they are a step further to get the problem solved. It goes without saying that once you know the root of a problem, you are close to solving it.

Getting a grasp of how your heaters work

If you are a person who has to witness at least four different seasons in a year, then getting a heater becomes a priority. This is why we have so many people using heaters around here. However, for many people who use furnaces, they only use it with an intent to derive the comfort they seek from the heater. Many of them do not have a grasp of how these heaters work. Therefore, when anything goes wrong with the heater; however little it may be, they become fazed.

By now, you should know that there are several types of heaters. Although many of these heaters share several similar qualities, they still have certain unique features which make them stand out. While some heaters make use of gas and other fossil fuels to run, other smaller heaters make use of electricity. However, one primary component that is to be found in all these electrical furnaces is the electrical resistor.

The sole purpose of a heater is to heat your home. Once a heater is put on, the nichrome wire components otherwise referred to as wiring coils get heated up by the electrical current that is immediately produced. As a result of this process, electrical energy is turned into heat as the current finds its way through the resistor. This is the reason why electric heaters are also referred to as resistance heating units.

The next step is more business-like. If your heater has a fan, it will draw cold air into the heater. This air passes through the heating elements, gets warmed, and is eventually directed back to the room. As a result of the fact that this warm air is transferred by air, it is called convection heating. These convection heaters are always recommended for quick circulation of heated air around a room.

In cases where the heater has no fan, the air comes in through the bottom layer of the heater, then passes over the coils to transform into the humid air. Following this, it would find its way out through the top of the heater. This kind of heating is referred to as radiant heating, and it is an excellent choice for quickly heating a very small environment.

Why is my heater making so much noise?

Ordinarily, furnaces should not be making a sound that would make it unbearable for your children to play, or for you to sleep. Once this starts to happen, the noise has become overboard, and something is wrong. In the next section, we break down these kinds of noises and what could be causing them to happen.

1. Excessive noise resulting from the blower motor
It could be that when you put on your furnace, it starts out with a very loud screeching noise much like the way a tire screeches. If this is the case, then the blower motor is most likely the guilty component. The function of the blower motor is to force warm air out of your furnace and also through the air ducts.

Due to the nature of this activity, the blower motor needs constant lubrication to ensure that its function goes smoothly. If this is not done, the fan may be hampered in its smooth working, and this could very well lead to a screeching sound.

2. Excessive noise resulting from a loose or damaged belt
Some furnaces have a belt as a critical component. These kinds of heaters are said to have a belt-driven motor. If the belt becomes loose, it can start to give off a squealing sound which is irritating. The squealing noise could also be resulting from your heater’s moving components which are meant to be regularly lubricated.

Your technician is supposed to lubricate these moving parts at every maintenance schedule. Over time, your belt can loosen up and can also get damaged. While you can, however, fix a loose belt, you are strongly advised against doing the same for a broken belt.

3. Excessive noise resulting from the blower wheel
When the noise comes from the blower wheel, it often comes as a loud clanking or scraping noise. This is also referred to as a metal-against-metal sound. Many times when this happens, it is because the fan has become loose and is creating an irritating sound by hitting against the blower house casing. Well, at best, the wheel may just be slightly damaged and would need minimal repair. But, at worst, it could be that the wheel is completely damaged and has to be replaced by an HVAC professional.

4. Excessive noise resulting from dirty burners
There is a very high possibility that a loud bang comes from your dirty burners when you turn the furnace on. This is especially dangerous and needs to be quickly addressed because it could cause a delay in ignition. The problem here is that a delayed ignition has the potential to cause an accumulation of gas and in turn an explosion.

Another factor, which can cause a loud bang, is inadequate air-to-fuel ratio. If the air to fuel ratio of your furnace is unbalanced, it would not be able to work efficiently. To work properly, there should be an adequate mix of gas. If there is too much air without an almost equal amount of gas, the result is a loud booming sound.

Another situation that can cause this booming sound is when the metal air ducts are contracting and expanding as a result of the change in temperature. Although this is quite natural, if it gets too worrisome, you may want to call in an HVAC professional.

5. Excessive noise resulting from a faulty heat exchanger
Sometimes, you could be hearing a rattling sound coming from somewhere in your furnace. If this happens, it could be that there is a loose panel or screw. This can easily be rectified by retightening the screw to fit properly where it belongs. But, in other instances, the rattling sound may not be coming from a loose panel.

Sometimes, it may be as a result of a faulty heat exchanger, and this is a much more dangerous prospect.

The fault in the heat exchanger may have been caused by a crack or a leak. A cracked heat exchanger may be caused by a lack of proper airflow. When airflow gets restricted by dirty filters, blowers can get heated up, leading to cracks and splinters. This can lead to carbon monoxide leaking into your home, and as such, needs to be quickly addressed.


A note of warning

Look out for these noises in your furnace:

  • Metal against metal
  • Loud scraping
  • Rattling
  • Rumbling
  • Screeching
  • Humming

The first course of action is to never ignore any of these kinds of noises once you notice them. They could lead to dangerous and expensive faults.

Fixing and Reducing Furnace Noise: How to do it yourself

1. Fixing the weak spots
If your ductwork happens to be faulty, your furnace will produce a sound as a result of the oil-canning. First of all, you have to find the weak spot. Once this is done, get a thick piece of metal and screw it on that spot and boom – you are good to go.

The problem of a weak spot can also be fixed by denting with a hammer. However, if you are not good with a hammer, it would be better to stick with the metal screwing method.

2. Fixing the gas ignition
A potential problem with a gas ignition can be identified in two ways. First, if when you put on the furnace, the door starts to shake, and secondly, if you notice some unusual flames after putting on the furnace. If you notice either of these, then you may be dealing with a very serious problem.

Although newer model furnaces are programmed to put off your furnace once things like this start to happen, you still need to be sure the heater is turned off. In cases like this, you have to call your HVAC professional.

3. Fixing your Dirty Filters
The above fixes are useful when your furnace is giving off a banging sound. What happens when the sound is a whistling one? In this case, the problem is most likely with your air filters, and you would have to clean them. As a result of the fact that the holes on air filters are tiny, when they get clogged, the air forcing itself to pass through ends up making a whistling sound.

You can decide to clean it by unclogging it. This you would have to do by bringing out the air filter for a proper clean up. On the other hand, if you bring out the air filter, and you can’t unclog it, you may have to discard the air filter and buy a new one.

4. Fixing your duct-work
It is, however, possible that your air filters may be in perfect condition, and your furnace would still be making a whistling sound. In situations like this, you may want to check your duct-work. If you notice that there are gaps in your duct, you have to quickly seal it as soon as possible. You may have to call in an expert to help take care of this.

It is also possible that the air ducts in your furnace are quite small. All you have to do here is to leave the furnace door open for a while and allow air to come in. If this does not work, you may want to resize your air ducts, a job that can be taken care of by HVAC experts.

5. Fixing the Motor
The motor of your furnace can also cause your heater to make loud noises. If your furnace is old and the design is complicated, you may want to change the motor as a whole. This is because the motor might have worn out.

However, if the design is not so convoluted, you can bring about some fixes. One of such fixes is the application of lubrication on the bearings. Alternatively, if your motor has plugs, you just have to remove and lubricate them.

Final thoughts on a noisy furnace

As you may have noticed, the noise produced by your furnace depends on the cause of the malfunction. The cause of this malfunction ranges from air ducts to dirty air filters and all others as already discussed above.

Loud noises are a sign that there is something wrong with your heater. It is best to call in certified professionals that can help you take care of this issue. Call us in today!