Why Does My AC Smell? Here’s What These Five Smells Mean

When homeowners use their air conditioning for the first time each year, it’s common to smell a little burnt dust as the system starts up. This usually dissipates quickly and shouldn’t affect your air conditioner’s performance. However, a smell that doesn’t go away could be a sign that something is wrong.

The cooling experts at Lakeside Heating & Air Conditioning can help. We’ve sniffed out more than a few AC problems affecting Denver homeowners, and we’re confident we can do the same for you. If you smell trouble, call Lakeside for fast and effective air conditioning repair in Denver at 303-421-3572.

In the meantime, we may be able to help you recognize these smells and what they might mean. Here are five of the most common smells that an air conditioner can produce and what they mean.

1. Burning or Smoke

A problem with electrical components, such as melted wiring or damage to the circuit board, is the most common reason for your AC smelling burnt. Occasionally, a piece of debris gets lodged in the system and starts to burn. Whatever the reason, Lakeside’s AC repair in Denver has a reputation for getting to the source of these electrical problems to ensure a lasting solution.

2. Mold or Musty Odor

An odor that resembles damp, musty basements is usually an issue with drainage. As the AC unit extracts heat, it produces moisture that needs to be drained. Gunk and mold can accumulate in the drain lines over time, leading to a musty smell as the mold spreads. Clearing these drain lines is a key part of Lakeside’s Denver AC maintenance checklist.

3. Like Car Exhaust or a Chemical Smell

A chemical smell resembling car exhaust or other substances is a sign that there’s a refrigerant leak somewhere in the system. While repairing small leaks is possible, larger cracks in the coolant system aren’t cost effective to repair. Instead, it’s best to start looking for a replacement unit before requesting AC installation in Denver.

4. The AC Smells Putrid or Like Trash

While your HVAC system is designed to have a firm seal insulating it from the outside, nature has a way of slipping indoors. Unfortunately, wildlife stuck somewhere in the system can start to give off an unpleasant smell that sometimes resembles trash. This can have an immediate impact on your home’s indoor air quality, and may get worse as time goes on.

These incidents tend to happen deep within the ventilation as rodents, birds, insects and other animals seek shelter. Periodic duct cleaning is a good way to find and clear them out before the smell appears.

5. Rotten Eggs or Sulfur

Natural gas is one of the most popular fuel sources for HVAC systems, but air conditioners generally use electricity because they don’t need to combust this fuel to generate heat. However, the AC system still needs the furnace’s air handler for circulation, so there are certain situations where you might smell something rotten.

A chemical additive called mercaptan is mixed with the odorless natural gas to create a highly recognizable “rotten egg” odor. If heating components like the gas valve or heat exchanger are cracked, you may smell rotten eggs when the AC turns on.

Your safety is our highest priority, so we strongly recommend leaving your home immediately whenever you smell rotten eggs or sulfur. Once you’re safely outside, contact emergency services and the local gas company for assistance. After a potential leak is identified, you can contact a Lakeside technician to resolve the problem. A comprehensive safety inspection is a key part of our HVAC maintenance plans, including careful review of your heating’s fuel supply.

Clear the Air with Help from Lakeside

If you’re tired of holding your nose at home, call Lakeside Heating & Air Conditioning for support. We’ll find the source of the smell and take the necessary steps to keep it from reappearing. To schedule service, call 303-421-3572 today.