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6 Common Air Conditioner Smells Answered and How to Repair Them

April 21, 2021

When your air conditioner is spotless and running right, you shouldn’t be smelling anything odd. Unexpected air conditioner noises and odd smells are a hint that something is off. If your air conditioner is past its prime or you haven’t had a tune-up done within the last year, they can be a sure sign you need professional air conditioning repair in the Bay Area.

Here are six of the most frequent air conditioner smells and how you can solve them.

1. Central Air Conditioner Smells Like Chemicals

If your air conditioner smells bad when turned on, specifically a chemical odor, isn’t a positive sign. You could also notice your:

  • Air conditioner smells like paint thinner
  • Home air conditioner smells sweet

These sweet, chemical odors are frequently a hint that your air conditioner has a refrigerant leak. Your system uses this gas to shift heat through copper coils, which can crack over time.

4 Signs You Are Dealing with a Refrigerant Leak

In addition to the odd smell, here are four other hints that you are experiencing a refrigerant leak.

  1. Bubbling or hissing sounds when your air conditioner runs.
  2. Ice on refrigerant lines or the evaporator coil.
  3. Trouble keeping your house comfortable or reaching your programmed temperature.
  4. Increasing energy expenses.

How You Can Fix It

A refrigerant leak calls for professional repairs from a heating and cooling company like Contra Costa Heating & AC. Your cooling technician will pinpoint and mend the leak before recharging your system with refrigerant.

Fixing a refrigerant leak typically costs between $225 and $1,600, per nationwide averages assembled by HomeAdvisor. Your exact cost will depend on the location and severity of the leak, as well as how long it takes to repair.

If your air conditioner was installed before 2010, it’s likely it runs on R-22 or Freon refrigerant. This refrigerant is no longer being made because of its harmful effects on the ozone layer. Due to this, repairs can be significantly expensive so it may be wisest to schedule air conditioning installation in this instance.

2. Air Conditioner Smells Like Gas

If your air conditioner smells like rotten eggs, there’s probably nothing wrong with it. But there’s a good probability you have a natural gas leak in your house. Natural gas has a sulfur-like additive to signal you when there’s a leak, because the gas can be fatal in heavy concentrations.

How You Can Fix It

If you notice a sulfur or rotten egg odor, we advise:

  • Switching off your gas supply.
  • Opening windows.
  • Leaving your home as soon as possible.
  • Getting in touch with your gas company immediately.

3. Air Conditioner Smells Musty

Individuals who call us regarding this issue frequently mention their air conditioner smells like feet, dirty socks or a locker room when it’s running. Also called dirty sock syndrome, this smell is usually created by a dirty evaporator coil that has mold, mildew and bacteria buildup. Excess water can also make your home air conditioner smell bad. Dirty sock syndrome is most often seen in climates where you use heating at night and during the morning before switching to cooling during the afternoon.

How to Repair It

The best way to prevent dirty sock syndrome is to regularly replace your air filter and schedule routine air conditioning maintenance with Contra Costa Heating & AC. We’ll keep the evaporator coil clean and the drainage system flowing, since stagnant water can also produce noxious odors.

4. Air Conditioner Smells Like Vinegar

If you are dealing with air conditioner mildew smell or a pungent, vinegar-like odor, it might be the result of several issues, such as:

  • A filthy filter
  • Extra condensation
  • Clogged condensate pan or drain line
  • Moldy air conditioner or ductwork

How to Fix It

Check your filter first. If you haven’t changed it within the last three months and can’t see light through it, you should replace it. If that doesn’t fix the issue, contact Contra Costa Heating & AC at 510-343-9841.

5. Air Conditioner Smells Like Burning Plastic

If you’re dealing with an air conditioner burning smell or that your air conditioner smells like fish, there could be a couple of things wrong. These entail:

  • Broken capacitator that’s overheating the motor.
  • Motor that needs lubrication.
  • Broken fan belt.
  • Electrical problem.

Electrical malfunctions should be checked immediately to prevent a fire. If you smell burning plastic when your air conditioner is operating, turn it off and reach us at 510-343-9841 immediately.

6. Air Conditioner Smells Like Cat Pee

A strong ammonia odor means there might be mold present in your air conditioner or ductwork. The smell isn’t the mold itself, but the mycotoxins that mold produces.

How to Fix It

Mycotoxins are hazardous to your health. That’s why you should have a professional like Contra Costa Heating & AC look at your air conditioner and ductwork and clean it when necessary.

Our Pros Can Take Care of Odd Air Conditioner Smells Fast

You deserve to be comfy in your home and shouldn’t have an air conditioner that smells bad. When you need relief from your smelly air conditioner, contact us at 510-343-9841. We’ll determine the issue quickly and resolve it at a reasonable.