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7 Reasons Why Your Air Conditioner Smells

7 Reasons Why Your Air Conditioner Smells

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Every time you get home and turn on your air conditioner, your expectations are high. You expect to get sweet, fresh air to make you feel comfortable and relaxed. Unfortunately, this does not always happen. It can be quite the unpleasant experience when you are greeted by odious air conditioner smells instead. These smells then get transferred into the air, leaving your entire house smelling like a sewage.

Where are these smells coming from? There are several reasons why your air conditioner could be emitting those awful smells. An HVAC professional will be able to diagnose the air conditioner problems in greater detail. In most cases, one of the following reasons might explain why your air conditioner smells so badly:

1. The air conditioner is faulty.

Does your air conditioner smell like it might be burning? In most cases, it probably means the air conditioner motor is overheating. This could be caused by a wiring issue or any other mechanical problem. When this happens, turn off the air conditioner as soon as you can. This prevent the overheating problem from getting worse.

Burning smells are dangerous symptoms and should not be taken lightly. If the smell persists, evacuate the house and only go back after clearance by the fire department. Your next step is to call in an air conditioner repair service to make sure there are no electrical or mechanical problems with your AC system.

2. Mildew and mould are causing the air conditioner smells.

Mildew and mould are causing the air conditioner smells.

Mould and mildew are the results of excess moisture in the air conditioning system. The air conditioner is your home is basically a big dehumidifier that is removing moisture from the air every time it runs. Depending on drainage, slope and run time there can be standing water collected in the ducting and evaporator coil causing mold and mildew.

This situation can be taken care of by making sure the drain is clear, the drain pan is sloping in the right direction preventing standing water and installing a ultra violet light above the evaporator coil to kill any mold or mildew that may still be growing in the coil or ductwork.

3. You haven’t cleaned your air conditioner in a long time.

You haven't cleaned your air conditioner in a long time.

Your body starts to smell when you haven’t showered, your clothes also smell when you haven’t washed them, and the same logic goes for unclean air conditioners. If you haven’t cleaned your air conditioner in a long time, don’t be surprised when it emits a musky old smell.

These air conditioner smells are often caused by dirty evaporator coils, stagnant water, and clogged condensate drains. Fortunately, it’s easy enough to get rid of these smells. Just clean your air conditioning system thoroughly and don’t neglect this maintenance task again in the future.

4. The smells come from dead critters & rodents.

The smells come from dead critters & rodents.

During the winter, everyone wants to stay warm, including the many rodents, critters and birds from outside your house. It is during this season that pesky rodents crawl into ducts in search of some warmth. Sometimes, they get trapped inside and eventually die. The smell of their rotting flesh is notoriously rotten and rancid.

You may be tempted to remove the dead rodent by yourself, but it can be quite dangerous since these creatures may carry diseases. To clear this bad smell, you would need to involve a professional to remove the dead animal remains from the ducts. Afterwards, clean the ducts to get rid of the rotten smell.

5. The smells come from cigarette smoke.

If you have the habit of smoking in your house, you might want to rethink your choices. Smoking in the house leads to smoke smells accumulating in the filters and the evaporator coil of your air conditioner. Instead of the nice, cold air you would typically expect from the AC, you would be greeted by a stale, cigarette smoke smell instead.

Cleaning the air conditioner regularly should get rid of the cigarette smell. For obvious reasons, you should not smoke anywhere near the AC system to stop this problem from recurring.

6. There could be a refrigerant leak.

If it smells like a chemical leak, it probably is. There is a good chance the refrigerant gas is leaking if it smells like gas every time you turn on the air conditioner. In such an instance, get a HVAC professional to inspect whether there is an actual leak. If there is one, you should always get the leak repaired before refilling the gas.

7. Your air conditioner is running inefficiently.

According to the manufacturers’ specifications, air conditioners should be used to their full capacity. When your air conditioner is running inefficiently, it may not be able to dehumidify the air as effectively. This eventually results in a murky smell due to lingering humidity. At this point you should have a technician come to your home and check the refrigerant levels and air conditioner to ensure it is running optimally.

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