The idea behind buying an AC unit is that it can entertain us with a refreshing cool breeze. However, if the air coming out of your AC starts to smell eerie, that defeats the unit’s whole purpose. Moreover, a smelly AC unit means that there can be a serious problem lurking in the unit that you need to rectify. Therefore let’s discuss some AC problems and related telltale smells that need your attention.

Leaking Refrigerant Gas:

An AC unit runs a gas that aids in the process of cooling the air. Freon is the common gas used for this purpose. However, due to breakage in the lines carrying the gas, there can be a leak. This will lower the performance of your AC unit; even you can notice freezing on the refrigerant lines. Another sign of Freon leakage is a smell similar to car exhaust.

You need to address these issues as soon as possible. This is because the Freon gas can accumulate to hazardous levels. Hence, to avoid that make sure your rooms are well ventilated.

Fried Up Circuits And Electronics:

At times, you can smell a burning odor out of your AC unit. Most probably, this type of smell indicates faults with the electronic systems of your AC. These components can be burning either due to excess current or loose wirings. However, continuously running the unit will inevitably damage these components more, so we advise you to switch off the system at once.

On the contrary, a similar smell can emanate from the burning of dust that has settled inside the unit due to a period of inactivity. Nonetheless, this smell doesn’t last long and wears off quickly within minutes of operations. However, if the smell stays and gets pungent with time, then the AC’s electronic system might be in hot water.

Dead Critter Inside Your Unit Or Ducts:

When you don’t use your AC unit for a long time, the period of inactivity is an open invitation for animals, birds, or insects to nest inside the ductwork. However, operating the unit again can trap them.

Eventually, the dying animals rot and exude a rotting smell; that’s quite similar to rotting eggs. Nonetheless, ductwork cleaning will help clear up the mess and get rid of the bothersome smell.

Accumulates Of Water in Drain Pan And Drip Lines:

AC units produce cooling using the phenomenon of condensation. Hence, water and your AC unit are pretty much inseparable. At times, moisture can accumulate in the lines and ducts, which causes the fungus to grow. Therefore, the growth of the fungus is marked by an earthy, musty smell.

This is one of the most common types of smell coming from an AC unit. However, there is an easy solution to get rid of this smell. You can start by changing the filters and getting the lines thoroughly cleaned by a professional.


Interestingly, most of the problems discussed above can be avoided by regular maintenance of the HVAC unit. Therefore, never miss out on your maintenance schedule, and you can rely on Crump A/C and Heating for all your HVAC needs. You can call us at 281-533-9200 for more inquiries.

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