4 Common Heating Smells and What They Mean

In Phoenix, that first chill kickstarts a new season and a break from the desert heat. After months of non-stop air conditioning, your heating system finally gets the spotlight. As you change your thermostat from cool to heat, the first startup of your heating system is unpredictable. Especially if you are not on a routine maintenance schedule, a heating system that sits dormant for months and is suddenly turned on can bring unusual symptoms to the forefront. At times you may experience the heating system emitting jarring smells. Each type of smell connects to a different issue that is occurring. Below are the four most common smell types you may encounter, the possible source, and how to address it.

1. Dirty Sock Syndrome

More commonly found in heat pump systems, homeowners who turn on their heat for the first cold snap of the year may catch an odor that is the equivalent of dirty gym socks. Typically, this comes from the evaporator coil, which spent the summer cold and wet from consistent condensation. When dust and dander stick to this moisture heavy component, it begins breeding bacteria and mildew. When the heat turns on, it essentially bakes this accumulation, creating the odor that is most commonly compared to dirty socks.

The Fix

Schedule a tune up with a licensed HVAC technician. If the evaporator coil is the source of the smell, they will conduct a professional coil cleaning to remove any bacteria or mildew on the component. Additionally, when you have this service visit, have the technician flush your condensate line to ensure that it is draining properly, as pooling water can contribute to the odor. Changing your air filters is also good practice, so they can capture as much as possible and minimize pollutant intrusions from attaching to your evaporator coil.

2. Rotten Egg or Skunk

If your home runs on a furnace, this is one of the most critical odors you do not want to ignore. Furnaces can run on different fuel sources including natural gas and propane, which are both odorless. In an effort to help homeowners detect a gas leak, suppliers will add a chemical called mercaptan into the gas. This chemical smells like, you guessed it, rotten eggs or skunk, and it's foul because manufacturers want you to detect a gas leak. If you detect any rotten egg or skunk odor, you must evacuate the home immediately and call 911 or the local gas company's emergency hotline.

The Fix

The moment you detect a rotten egg or skunk smell, the very first step is to evacuate the home. Do not flip light switches, use phones inside, or touch electrical appliances on your way out, as any small spark can ignite gas. Once everyone is safely out, call 911 or the local gas company's emergency hotline.

Once emergency services have located and repaired the leak and given the all-clear to reenter the home, contact a licensed HVAC technician for a furnace inspection and repair to ensure all components are in working order. Even if the source of the leak was not the furnace, it's imperative to take this time to have it checked just to be safe.

3. Burning Dust

During the summer months, it's normal for dust and dirt to accumulate in and around your heating system from lack of use. When you first turn on your heat for the season, the dust and dirt will burn off, creating a burning dust odor. This smell should fade during the first heating cycle or two. If it lingers, consider the suggested fix below.

The Fix

If the burning dust smell persists longer than usual, check your air filters. A clogged air filter restricts airflow and allows dust to settle on your heating system's internal components. Changing them out may resolve the issue. If it doesn't, contact a licensed HVAC technician for a service visit so they can run a full check to determine the cause of the burning dust smell.

4. Burning Plastic, Electrical, or Metallic Odors

Any smell that resembles an electrical burn, hot metal, or heated plastic indicates that the system is overheating. A situation that involves overheated wiring or electrical components is susceptible to system fires. Parts of the system that typically face this dilemma include:

• Overworked blower motors with worn bearings or failing windings
• Overheated, loose, or melting electrical wiring and circuit boards
• Foreign objects or debris lodged near heating elements and internal components

The Fix

If you catch this kind of smell, head to your thermostat immediately and shut off the system. Then schedule a heating repair visit with an HVAC professional. They are the experts that can assess the system and identify where the plastic, electrical, or metallic burning smell is coming from and conduct the appropriate repairs.

Keep Your Heating System Maintained with George Brazil in Phoenix, AZ!

It's always crucial to keep your nose on alert the moment you run your heating system for the first time after months of non-use. However, a great way to avoid the surprise is to have routine heating maintenance conducted before use. George Brazil's Worry-Free program covers that visit, and our technicians leave a system report card on every call so you know exactly what they found. Staying on top of routine maintenance can make all the difference, so there are no surprising smells when you're ready to have a warm, cozy home. Experience George Brazil's quality heating services and schedule your visit today