The last thing you need, when you head indoors after another insanely hot day, is for your aircon to send out not just cool air, but a nasty smell. Not only do unpleasant smells…smell unpleasant, but these smells may be the harbinger of a problem that could affect your health.
The air coming out of your unit may be carrying with it mould spores, bacteria or even the cooling fluid if there’s a leak. This is not ideal for anyone and can be particularly harmful to anyone with asthma, allergies or respiratory issues.
If your air con smells, there could be a few factors affecting the device. If the source of the bad odor is not external such as pollution, here are the top reasons your air conditioner may smell bad:
Here are the top five reasons for a malodourous aircon unit
Mould or mildew
This is by far the most common issue with smelly aircon units. As your conditioner cools the air, it also removes water from it and if this water isn’t drained away properly, it presents the perfect breeding ground for mould. You’ll notice a characteristic musty smell if your aircon has this issue, so you’ll need to bring in a trained HVAC technician to check over the drainage and to remove the mould or mildew fungi causing the problems.
Leakage of coolant or other fluids
If you get a really pungent, skunky sort of smell coming from your aircon unit when it’s working, you may have a leak in the engine or in the cooling system.
This is actually quite hazardous as the gas may be methyl mercaptan which can cause eye, throat and skin irritations and at higher concentrations can even cause vomiting and unconsciousness. More worryingly, methyl mercaptan is flammable, so you really need to take action immediately. Turn off your aircon straight away and call in a trained techie so locate and fix the leakage so you can stay cool and safe.
A dirty or clogged system
Another common issue is a lingering, musty, wet dog, wet sock, old trainer kind of smell. This smell often comes from stagnating water hanging around in the system rather than draining away properly. If this is an issue for you, then you need to get your maintenance guy in to clean the unit up, identify any niggles and to show you the best way to keep your aircon in good condition.
Clogged filters prevent your air conditioning unit from working properly and if fluids and gases aren’t moving around as freely as they should be, certain parts can freeze while others overheat. Clogging can also damage the compressor and the heat pump, so any weird smells emanating from your aircon need investigating so that you’re saving your money as well as your nose.
Animal waste in the ducts
During the winter you probably use your aircon a lot less and this is when it can provide a cosy home for various forms of wildlife. As you can imagine, these critters leave their waste products behind or, even worse, dead bodies. Once you turn your aircon back on for the summer, you’ll soon notice any animal activity, so if you think this has happened to your unit, you’ll need to call a techie in to inspect it for damage and to clean it all up.
Your air conditioner is important for your health
If your aircon unit smells bad it’s not just a nuisance, it can be dangerous for your health, especially if there are toxic gases, mould or animal waste involved. Breathing in air which contains ammonia, methyl mercaptan, mould or bacteria can lead to breathing problems, eye infections, headaches and even loss of consciousness.
While there are a few things you can do yourself to keep your aircon unit clean and running well, you’re best advised to have it inspected once a year by a professional. If you notice any unpleasant smells from your unit, you should take action as soon as possible, just in case the smell if the sign of a serious problem which could make you or your family sick.