air conditioning

Common Reasons for Unpleasant Air Conditioner Odors

No one ever wants to switch on their air conditioning unit in the hopes of feeling more refreshed, only to discover a foul scent assaulting them. Actually, it’s never a good sign if the aroma coming from your air conditioner makes you nauseous.

It’s probably time to call an air conditioning service if foul smells begin to emanate from your unit. In order to know what you’re dealing with, it’s a good idea to figure out what’s creating the stench.

Some of the most typical reasons for foul-smelling air conditioning are listed below.

Mechanical or Overheating Issues

It’s recommended to turn off your air conditioner if it smells like melting plastic or burned wires. Examine your electrical outlets and wiring to discover if any are overloaded. Be careful when doing this to avoid being shorted out or, worse, electrocuted.

Additionally, you can experience overheating as a result of a malfunctioning motor or internal component damage. Call an air conditioning repair firm to examine your machine; they should be able to resolve the problem.

If your wiring is damaged, you should also contact an electrician. When you turn off your air conditioner and still detect a burning smell, call the fire department immediately and turn off the breaker.

Leaking Sewage

You may have a sewage leak if you notice a foul odor emanating from your air conditioner. This indicates that there is a drainage pipe issue that needs to be investigated right away.

Any issues with your P-Traps and sewer lines may cause an odor to come from them and spread throughout your home because the AC circulates air. 

To make sure you are not dealing with major damage, you should have a plumber check this out.

Mildew and Mold

Mold and mildew could spread through the ductwork if the HVAC system has excessive moisture or humidity. Fix all water leaks, enhance drainage, schedule yearly HVAC tune-ups, and routinely swap HVAC filters to help prevent mildew and moisture issues.

If there is exposed earth in your basement or crawlspace, you might want to look into coverage options. A whole-home dehumidifier is the greatest approach to safeguard your possessions and stop mold and mildew from growing in your house and HVAC system. 

The dehumidifier automatically removes the right quantity of moisture from the air and deposits the condensate outside when it is connected directly to your existing HVAC system.

Make sure the firm you pick offers a thorough cleaning when arranging your air conditioner’s tune-up. 

Your condensate drain line will be cleaned, the evaporator coils will be cleaned, and any mold or mildew issues will be found during this annual inspection.

System Blockages

Your air conditioner may have a buildup of condensed water that is not draining properly if it smells like a filthy, wet dog. To check for clogs, remove them, and optimize the setup to ward off future blockages, it is advisable to get it checked.

Dead Insects and Pests

If your air conditioner is emitting rotting odors, a pest may have become caught there and perished. In this situation, you must immediately dispose of the carcass. 

An air conditioning service can sanitize everything and find any bugs or vermin hiding in the unit. It’s also best to address any bug problems in your home as soon as feasible.

Gas Leaks

If you smell rotting eggs, there may be a gas leak. If you can’t identify the source of the scent, you should notify emergency services because this is no small matter and might be very harmful.


You don’t want the scent of the garbage disposal to emanate from your air conditioner. Check your AC to determine the cause of any persistent odors emanating from it. If you notice any of these smells, be sure to call a qualified technician to diagnose and fix the problem.

If you feel like you need an air conditioner repair, don’t hesitate to call AutumnAir. We’re a family-owned company in Pelham, providing HVAC and AC repair and replacement as well as residential and commercial electrical services. Call today to schedule an appointment.

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