Why Is There a Burning Smell Coming From My Home’s AC Vents?

Have you been smelling a strange smell, as if something is burning, every time you turn on your air conditioning unit? The smell is often an indication of a more serious problem happening within your unit, so it’s important not to ignore it – instead, addressing it as soon as it happens is the best approach. But what causes a burning smell from AC vents in house? And are there different types of burning smells? Let’s talk about it.

Understanding the Burning Smell

Oftentimes, the reason behind the burning smell can be guessed based on the smell itself – depending on what is going on with your air conditioner, you will either smell electric, rubber or dusty burning smell:

• Burning electric/plastic smell – If your air conditioner smells like burning plastic or electric, it often indicates an issue with wiring or a faulty capacitor. It’s especially when concerning when accompanied by a popping or sparking sound.
• Burning rubber smell – In many cases, this indicates that the issue behind the smell is a faulty fan belt.
• Burning dusty smell – This is an especially common case when the air conditioning unit has been inactive for a while, for example, if you went on a longer vacation. If the dust accumulates, it can heat up once you turn on the AC.

Common Causes of Burning Smells from AC Vents

Trying to figure out where the burning smell is coming from? Scratching your head and wondering, “Why does my AC smell burnt”? There are a few possible culprits you should consider.

Dirty Air Filters

Your air filter stops the air contaminants such as debris or dust from getting into your home – without it, or if it ends up clogged, all of them end up getting into your blower, causing it to overheat after a while. The burning smell is a result of that.

How to fix it: To determine whether that’s the issue behind the smell coming from your vents, you should check the air filters. Are they dirty? If so, the solution is to clean them using warm water and mild detergant, or, if they’re really damaged or made from a material that is not reusable, to replace them completely.

Dirty Ductwork

Similarly to a dirty air filter, the burning smell could be the result of the debris from outside, such as grass cuttings or pine needles, getting into the air conditioning system and getting overheated. This is an especially common issue if you haven’t been using your AC for a prolonged period of time.

How to fix it: When it comes to duct cleaning, the easiest and safest way to fix it is by scheduling a professional service. However, if you decide to clean your AC ducts yourself, make sure that you don’t leave them wet – they should be completely dry before turning the AC on again.

Broken Fan Belt

If the burning smell is accompanied by a squealing noise, chances are that the reason behind it is actually a damaged fan belt. The belt keeps fan blades connected to the motor, and when it breaks, it can cause them to rub against each other, resulting in a burning smell.

How to fix it: Replacing a damaged fan belt is not something you should be doing yourself, so the solution here always is to call a professional for help.

Overheated Fan Motor

Another reason why you might be smelling a burning smell from your AC is an overheated fan motor. Usually, however, the smell source is not the motor itself but the components around it, typically the insulation, that melt.

How to fix it: This is another issue that requires you to ask for professional help – trying to fix it yourself can result in further damage to your unit.

Electrical Failure

Do you not only smell a burning smell but also hear a popping sound? If so, the reason behind it can be electrical failure – the popping sound is caused by sparks. The heat from them can build up, causing elements of your AC system to melt, resulting in a burning smell.

How to fix it: So, what to do if you smell electrical burning? Unless you have experience dealing with electric, don’t try to fix it by yourself – get in touch with a professional that has been trained specifically to handle AC electrical problems. Otherwise, you might not only damage the unit, but also injure yourself.

Refrigerant Leak

Another common reason that can cause your AC to give off a burning smell is a refrigerant leak – the refrigerant is responsible for moving the air between your home and the outdoors so that your house stays cool. If there’s a leak, there’s not enough of it to do its job properly, meaning that your AC could become prone to overheating – thus the burning smell.

How to fix it: If the leak is small, you can try to fix it yourself, for example, using epoxy – once the leak is fixed, you just have to add more liquid, and it’s done. For larger leaks, however, it’s best to call a professional, as a bigger issue might be happening somewhere within your unit.

When to Be Concerned

Generally speaking, any time you notice a burning smell coming out of your AC, you should be concerned, as that means there’s something wrong with it. However, particularly worrying situations are when:

• The smell persists for longer periods of time and cleaning your filter brought no results.
• Your AC smells like burning plastic or eclectic – in this case, turn your AC off immediately to not cause further damage.

The best idea is always to get in touch with a professional whenever you sense something is wrong with the air conditioning unit – unaddressed issues can become a larger problem in the future, especially when electricity might be involved, but you don’t know about it.

Preventative Measures

There are a few things you can do to prevent the burning smell from happening to your air conditioner:

• Clean the air filter regularly – A lot of times, simply replacing the filter regularly can significantly improve the life span of your AC unit. How often that should happen depends mostly on the manufacturer and the type of air filter you use. Some should be replaced monthly, while others are good for three to six months.
• Have HVAC professionals perform maintenance regularly – Performing regular maintenance can make a world of difference when it comes to how long your air conditioner unit will last. It allows technicians to discover issues before they become bigger and require expensive repairs. An annual or semi-annual HVAC checkup will be enough.
• Pay attention to unusual noises – If everything works well, your air conditioner will be working silently in the background – any kind of noise indicates that there’s something wrong with it, either there’s some damage or your AC is already old, and you should consider replacing it.

The Bottom Line

A burning smell coming out of your air conditioner should always be a reason for concern, as it indicates that something is wrong with your unit. Some of those, you can address yourself – however, in many cases, professional help is required, especially if the issue runs deeper than a dirty air filter. By reaching out to a qualified technician, you can prevent further damage to your HVAC system.

At Meadow Air, we understand the importance of acting quickly and efficiently when it comes to something as serious as a burning smell. That’s why, if you feel it in your home in the Phoenix, AZ area, you should get in touch with us as soon as you notice it – our technicians will be able to help you even as fast as on the same day.

Get in touch with u, and let us help you bring your AC unit to its former glory today!