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What to Do When Your Air Conditioner Smells Bad

Author Rod Marchant-Smith | Peninsula Air Conditioning

Newport resident, Margaret asks

“We’ve noticed a bad smell coming from our air conditioning unit. It seems to be much worse at the back of the house, near the main bedroom. We always have our unit serviced regularly so we’re really not sure what could be causing this smell?”

A smelly air conditioner can be caused by a whole host of different things. Of course, if your air conditioning unit smells, it’s always best to have it looked at because if left, it has the potential to cause illness.

When your air conditioner begins to emit a foul smell, it’s a sure sign that it most likely needs a professional service and cleanse.  Mould and bacteria can cause bad odours to build up within the system itself which can cause respiratory issues or flu-like symptoms. It’s not hygienic, or pleasant.

If your air conditioner is starting to smell, we’d recommend a thorough clean of the internal system.  This requires us to dismantle the indoor unit and clean it using a biodegradable product called Aerisguard.  It’s a bioactive, multi-enzyme cleaner that we use to clean the fan coil.  We then apply a non-toxic, non-corrosive, and biodegradable product to the filter to prevent the mould and bacteria regrowth and prevent it from coming through the filters.

But how does mould get there in the first place?

When hot air is drawn through the air conditioner on humid days, condensate can form.  It mixes with dust and dirt and remains in the system, creating ideal conditions for mould to grow.

Remember, the air is being recycled.  If the system is not adequately maintained and cleaned, you can end up with a buildup of germs and bacteria.  For businesses, particularly office spaces, you’ll want to ensure your systems are kept clean all year round.  By doing so you help prevent staff calling in sick regularly and ensure a healthy workplace.  For larger spaces, a ducted system might be better suited. In fact, the National Asthma Council Australia recommends ducted systems as they can help prevent triggers from affecting people that suffer from asthma.

Common causes of bad smells and odours

Smells like – Bad foot odour or dirty socks

Possible cause – Air conditioning units that smell like dirty socks or bad foot odour usually indicate a dirty or clogged system.  This is due to water sitting inside the unit, it doesn’t drain correctly and in turn, becomes stagnant and begins to smell.

Fix – A full service, and professional clean will resolve the issue.

Smells like – Exhaust fumes

Possible cause – Often homeowners might misinterpret this as a gas leak.  Air conditioners aren’t gas-powered so there shouldn’t be any causes for concern.  Typically when your air conditioner smells like fumes, its caused by mechanical parts of the internals leaking fluids.

Fix – Call us immediately. Any type of potential leak is best left to a qualified professional.

Smells like – Gun powder

Possible cause – Typically this is caused by an electrical fault.  In most cases, it will be a circuit board or fan motor shorting out.

Fix – Call us immediately.  Any electrical faults require urgent attention and should only be carried out by a qualified HVAC professional.

Smells like – Roadkill

Possible cause – Typically smells like this are pretty obvious.  It’s usually always caused by dead animals (rats, birds etc) that crawl into the ductwork and either get trapped or die of natural causes.  Smells from dead animals can be pretty awful, not to mention the potential for diseases, so it pays to have the system inspected as soon as possible.

Fix – Your ductwork will need to be inspected, cleared and professionally cleaned to get rid of any animal remains.

Smells like – Mildew

Possible cause – Units that begin to smell of mildew are usually the result of mould, or fungus that has built up inside the system.  This can happen when the system doesn’t drain properly, which results in dampness or moisture accumulating in the piping or filters.  Dirty filters also can give off the smell of mildew.

Fix – A professional clean using industrial-grade cleaners is recommended.  Call us today to book a service.

Air conditioning cleaning costs

If your air conditioning unit smells, it’s most likely going to require an internal cleanse which involves the following-

  • Our team will first perform a standard service.  The price is based on accessibility to the system and whether or not we need to send one or two technicians.
  • We offer servicing for residential systems on a price scale based on whether or not you are an existing client ($179), a new client ($199) or whether you’re part of our maintenance programme.
  • An internal clean will likely cost an additional hour’s labour, plus $65 for the products needed to perform the task.  This is charged at an hourly rate of $190 per hour for an existing client for two technicians, and $199 for a new client for two technicians.  We usually send two technicians to make sure that the process is done swiftly.
Got a smelly air conditioner?

If your air-conditioning system begins to emit a foul smell, we don’t recommend you attempt to clean it yourself. You would need to dismantle the service ports on the outdoor unit, which needs to done safely by a trained and qualified professional. Doing so could lead to damage and invalidate the warranty.

If you’re concerned about the state of your aircon, please give us a call, and we can discuss your options. Apart from the discomfort caused by a bad smell, it could be harming the health of your family or pets. It’s best to get it addressed as soon as you become aware of it.

Free, No Obligation Consultation.

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