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Common causes of smelly air conditioning

One of the most common causes of calls to our service department during the cooling season is smelly air conditioning. Here’s why it happens and what you can do about it!

Why is my air conditioning unit smelling?

During the cooling process, your air conditioner is dehumidifying or removing water from the air. This is why each air conditioning indoor unit requires a drain to remove the water from the unit.

As air from the room is picked up by the air conditioning indoor unit and blown over the evaporator, it is common for perfumes, body odour, or deodorants to be picked up by the unit and dehumidified.

One of the base chemicals of perfume and deodorant is animal fat, which in its natural state, without additional chemicals to make it smell nice, is smelly and can often smell like fish, sweaty socks, or animal urine.

These animal fats then get deposited on the air conditioning coil. In most cases they wash away with the condensate water (water removed from the air), but sometimes they get lodged on the coil.

Once they become dry and air is blown over them, they omit a bad odour as they go back to their base chemical after the water based scent is washed away by the dehumidification. Although unpleasant, this smell isn’t dangerous at all.

It is therefore not surprising that this smell occurs more commonly in call centres or environments with lots of people. It can also occur in smaller areas where occupants are within close proximity to the unit, such as in domestic bedrooms and kitchens. You may also notice this happening on your car’s air conditioning, as this is also a confined environment.

Please note that the information above assumes that the air conditioning indoor unit filters are clean and free from debris and dirt. If you’re unsure about this, please contact our service department for assistance.

What can be done to get rid of the smell?

Most of the time the smell can be washed away by simply using the air conditioning unit more frequently in cooling mode, thus creating more water to wash the base chemical away.

If the smell won’t go away then we can chemically clean the coil to remove the base chemical.

Specialist products, like Smelly Jelly, can be used in conjunction with the coil cleaning to help delay or mask any future reoccurrence.

For more severe cases, where the above chemical cleaning doesn’t work, we can fully strip down the unit to complete a thorough deep clean using our specialised pressure washer and chemical cleaning agents.

Although we can get rid of the smell by chemically cleaning the coil, unfortunately, we cannot guarantee the smell will be gone forever. External sources of odour, such as perfumes and deodorants will likely always be present within the area being air conditioned.

To arrange for your smelly air conditioning to be investigated, or for the coil to be cleaned by our highly qualified, technical engineers, please contact our service department to arrange a callout. Learn more about Kool It air conditioning repairs and servicing contracts.