There’s nothing quite like an unpleasant Air Conditioning to ruin your day. A foul smell produced by an air conditioner could be a sign of a severe problem and potentially a hazardous situation. So if you turn on the air con and a bad smell emanates from the vents, then you’re going to need to request maintenance.

Bad air conditioning smells are nothing to be scoffed at. It is possible that your air filter just needs cleaning. But it’s also possible that the circuits are fried, and a potential fire hazard is heating and cooling your home. So AC smells should be investigated right away.

Here are 7 of the most common air conditioning smells and their causes:

1. Mildew or Mould Air Conditioner Smells

If your air conditioner emits a stale or musty aroma around the house, it could result from a leak somewhere in the system. It’s not uncommon for the drip lines, drain pan or evaporator coil to clog and then leak. This leaking water can pool and become a suitable breeding ground for mildew or mould. Mildew and mould are two of the more common causes of bad smells.

Alternatively, a musty aroma can be caused by a dirty air filter, particularly in regions with high humidity. The additional moisture can settle on the filters and produce unpleasant smells, and dirty filters can also affect air quality. So we recommend that you clean the filters every three months by brushing the dust off and washing them in soapy water. Anyone can clean a dirty filter. However, you will need the assistance of an expert to fix a leak.

2. Air Conditioner Smells Like Burning

Air conditioning carries its fair share of components and circuitry. And like all electrical appliances, there’s room for faults. A burning odour will likely indicate that one or more of the electrical components are burning. This can be caused by water damage, overheating, a build-up of dust and many other issues.

If the smell dissipates quickly, then there may be nothing to worry about. But if the smell sticks around for longer than a few seconds or the unit produces smoke, you should shut it down immediately and call an HVAC technician before further use. Booking a scheduled service can limit the chance of build-up and clogs, so it’s always wise to organise an annual service.

3. AC Smells Like Rotten Eggs

The rotten eggs smell shares many similarities with natural gas, so if you’re smelling eggs, then there’s a good chance that the air conditioning smells are caused by a gas leak. The gas itself has no odour, so the distinct smell is added as a safety precaution.

As a gas leak can lead to carbon monoxide poisoning, you must act immediately if your air con or any appliances, for that matter, give off a rotten egg smell. First, open windows to ventilate the area. Then, shut the air conditioner down and consider closing off your home’s gas connection at the mains if the problem is not limited to the air con. Then you will need to call a licensed gas fitter or air con professional for a repair before it’s safe to use the system again.

4. Air Conditioning Produces a Chemical Smell

An air conditioner emitting a chemical-like smell, something reminiscent of paint thinner or chloroform, can signify that your system is leaking essential fluids. Refrigerant gas is present in reverse cycle air conditioning and is relied upon to treat the air before it’s dispersed throughout your home. A chemical odour suggests that the refrigerant is leaking, which can be harmful to your health and the environment while also limiting the performance of your air con.

Only licensed air conditioning technicians are legally permitted to perform an air con regas. So shut down your AC if you smell chemicals, crack the windows and give us a call.

5. AC Smells like Exhaust Fumes

No natural gas supply? That won’t stop an air conditioner from producing a smell similar to a car’s exhaust fumes.

Air conditioners have motors. Motors require lubrication. And so oils come into play. If the oil were to leak or the central unit was to overheat, it’s possible for that oil to burn and for those undesirable exhaust aromas to affect the indoor air quality.
The exhaust can be hazardous to your health if not ventilated properly. So contact your HVAC system professional and get that issue fixed.

6. Gunpowder Air Conditioner Smell

An air conditioning unit emitting a gunpowder smell can signify a serious problem. It’s likely that the fan motor or circuit board is fried and needs replacing. This can be caused by overheating, water damage or the circuits receiving the incorrect voltage.
The smell of fried electronics is not dissimilar to the fire-like smells mentioned above.

However, the damage here can be much worse. Once again, the fumes can cause respiratory problems. It’s advised that you shut down the AC right unit away and crack the windows before calling for repairs.

7. AC Produces Sulphur Smell

We saved the ‘best’ for last. If you’re trying to enjoy the comfort provided by an air con only to be struck by a methane or sulfuric odour, then there’s a good chance that an animal or rodent has died in your system.

Critters like rats, mice, lizards, birds and possums have all been known to explore the insides of a compressor or ducts only to get trapped within and die. It’s only a matter of days before they start to produce a distinct smell that you can’t mistake for anything else. The good news is that our technicians can address this problem and investigate if the system’s performance has been affected.

Air Conditioner Repairs

If you’re experiencing any of the above air conditioning smells, your best course of action is to have a professional inspect the HVAC system and recommend the appropriate fix. Repairs or a thorough clean will hopefully be all that’s required. But if key circuitry has burned out, it might be time to consider replacing the air conditioning system or looking into an upgrade.

Whatever the cause, give Metropolitan Air Conditioning a call, and we can schedule an inspection or provide emergency after hours service. Request a repair and improve your indoor air quality today!

Why It’s Important to get Temperature Right

This may seem obvious, but it’s imperative that you get your indoor air temperature right throughout the winter months, and the reasons go well beyond comfort. They include:

Virus & Disease Prevention: Too much exposure to cold air reduces the effectiveness of your mucous membrane. These membrane cells work to protect your body from pathogens and viruses. Without adequate protection, you can become more susceptible to common colds, the flu and other serious health concerns.

Asthma: When the winter air is too cold, its water content won’t evaporate as effectively, leading to higher humidity in the home. Asthma sufferers won’t need to be reminded that humidity can impact breathing. Breathing in humid air can trigger asthma as nerves in the lungs narrow and tighten the airways making it difficult to breathe.

Humidity also brings allergens, diminishing air quality through pollen, mould and dust – all of which can affect asthma.

Overheating: Setting the air conditioning temperatures too high can lead to overheating, especially at night when there’s the added warmth generated by bedding. Being overheated can cause sweating, exhaustion, dehydration, heat rash and heatstroke in severe cases.

The elderly are at a much higher risk of overheating in the home as the aging body can no longer regulate temperature effectively.

Running Costs: The harder your air conditioner has to work, the more energy it consumes. Setting to a high of 30 degrees in winter or a low of 18 degrees in summer may seem appealing, but it won’t be efficient. The additional energy required to achieve these results would cost more money than if you had settled for a comfortable middle ground.

Environmental Impact: Hardworking systems can be detrimental to the environment. They consume a lot of electricity. The more electricity used, the more greenhouse gases vent out into the environment. So when it comes to heating and cooling, an AC unit that has to work harder or one that’s not energy efficient will leave a more substantial carbon footprint.

What Temperature Should I Set My Air Conditioner in Winter?

So what is the best temperature for air conditioners in winter? The answer will differ throughout the day.

The ideal temperature for winter nights according to Healthline is between 15.6°C and 19.4°C for adults and between 20°C and 22.2°C for babies. These temperatures take into consideration sleep attire and winter bedding, so set the thermostat accordingly.

Of course, the best temperature for everyone is slightly different. Some people can run hot, and others run cold. So the ideal temperature for comfort will always differ. Your best course of action is to discuss it with your family to achieve a happy, efficient medium.

If your primary concern is running costs, Origin Energy suggests that you should never set your thermostat below 24°C during the day, as every additional degree consumes 5 per cent more energy. So setting your air conditioning to 20 degrees would use 20 per cent more power than an AC set to 24°C. Other sources go so far as to claim that every degree lower uses an additional 10 per cent of energy.

With heating and cooling being the heaviest hitters on your energy bill, sticking to the recommended temperature will improve energy efficiency and increase savings on your next electricity bill.

What Size Air Conditioner Do I Need?

The temperature indicated by the thermostat doesn’t necessarily represent the current temperature of the rooms in a home. It’s possible to set your air conditioning thermostat to 24°C only for the room to become hotter or remain colder.

If this is the case, your air con may be the incorrect size – as in, too powerful for a home of that size or not powerful enough. Here are the best air conditioners per room size: