bad smell coming from ac

Why Does My Air Conditioner Smell Bad When Turned On?

When an air conditioner produces an odor along with cool air, your home will no longer be a comfortable place to rest and relax. AC smells can be caused by a variety of factors, including dirt, mold, mechanical malfunctions, moisture, pests, and more. If your air conditioner smells bad when turned on, it’s important to take action right away. Poston Brothers Heating and Cooling can find the source of a smelly air conditioner and fix the underlying cause quickly. Learn the reasons behind common ac smells and what to do when you notice them.

Why Your Air Conditioner Smells Bad When Turned On

If your air conditioner smells bad when turned on, there could be something in the system that shouldn’t be there, or a normal part of the system may not be working correctly. Some air conditioner smells can be resolved quickly on your own, while others will require the help of a trained HVAC technician to conquer.

Here are some of the most common odors reported when your central air conditioner smells bad when turned on, and their causes.

Lingering Household Odors

Cigarette smoke, pet hair, cooking aromas, cleaners, and more – these things can all stay behind in your home, hiding in your air conditioning equipment instead of being expelled outdoors as exhaust. These particles become trapped in the system and produce an unpleasant odor whenever the cooling system runs.

These particles commonly become trapped in a dirty air filter or on a filthy evaporator coil. Regular maintenance and air filter replacements can help prevent this reason why your air conditioner smells bad when turned on. Whenever you notice these smells, perform some cleaning to your ac unit right away to eliminate them. The air filter should be replaced as needed, which can be every 1 to 12 months depending on the model and your home. The evaporator coil should be cleaned every 6 to 12 months.

Moldy, Stinky Feet Smells

If your ac smells musty, it’s likely that mold or mildew is growing somewhere in the system. Mold commonly grows within the ducts or on the evaporator coil of the indoor unit.

If your home air conditioner smells like stinky feet when turned on, this could also indicate mold or mildew growth too. This usually means that there is water trapped in the system somewhere, which can lead to the growth of mold and mildew. The drain pan may be full of stagnant water and the condensate drain system clogged.

  • Use a wet/dry vacuum to remove standing water from the drip pan. Clean the drip pan with bleach or vinegar to prevent further mold growth.
  • Remove materials clogging drain lines using a garden hose, long wire, cleaning brush, or another household tool. If you are unable to clear the line, call a heating and cooling company to make the repair.

A Foul, Rotten Smell

Homeowners often complain that the air conditioner smells bad when turned on before discovering a pest or vermin infestation in their home. Insects and small critters can access your home from outside and chew through materials to infiltrate the ducts. Rodent and bug droppings, a dead animals, and other pest matter cause odors. Commonly the area where they nested is typically the source of the odor that makes a strong air conditioner smell.

Have a pest control provider inspect the system and treat any active infestations. In addition to addressing any pests, it’s also important to have your ducts cleaned and check your air conditioning unit for signs the pests accessed these areas. Make repairs to vent covers and other exterior barriers to prevent access into your HVAC system.

Burning or Electrical Odors

One of the most common reasons an air conditioner smells bad when turned on is because of overheating components. Electrical odors can be caused by several different components, including circuit boards, fans, blower motors, compressors, and more. An air conditioner burning smell or an electrical odor can go hand in hand with damage and the need for replacement. If you’re noticing a burning smell, call an HVAC technician to make the necessary repairs right away to prevent as much damage as possible to your air conditioner unit and the impacted parts. 

Chemical Smells

When noticing an air conditioner smell that is sweet, chemical-like odors are commonly caused by a refrigerant leak. If you’re experiencing a sweet chemical odor similar to chloroform or ether, it’s likely due to coolant escaping the system. The best way to get rid of this smell is to ventilate the home. This will help to prevent exposure and toxicity. Call your heating and cooling company, as an HVAC technician must find the refrigerant leak, make repairs, and refill the system with the proper volume of refrigerant.

AC Repairs in Burlington, KY

If your air conditioner smells bad when turned on, the cooling system may need repairs. Call the Poston Brothers Heating & Cooling team to make an appointment for air conditioning system repair today.

Heat Pump vs Air Conditioner: Which is Best for My Home?

When replacing heating and cooling equipment, it can be difficult to decide whether to install a heat pump or an air conditioner in your home. Both HVAC appliances have their pros and cons, and the best option for each homeowner will depend on specific needs, preferences, and budget. Poston Brothers Heating & Cooling breaks down the basic similarities and differences between heat pump vs air conditioner units so you can make an informed decision about which one you’d like to use.

What Is an Air Conditioner?

Air conditioners are the most common cooling systems in the world. Split system central air conditioners use an outdoor air conditioning unit connected to an indoor furnace or air handler. They work by taking the warm air inside the house and moving that heat outdoors to be released into the atmosphere. This process is facilitated by refrigerant that cycles between the indoor and outdoor coils.

What Is a Heat Pump?

A heat pump is a split heating and cooling system that transfers heat from one area to another. An outdoor heat pump unit connects via refrigerant lines to an indoor air handling unit.

The heat pump can cool a space by removing heat from the home just like an air conditioner does. The big differentiator between a heat pump and an air conditioner is that a heat pump can also heat a space, which an air conditioner cannot do. The heat pump isn’t just a cooling system, it can also operate in reverse, moving heat energy from the outdoor air to the indoor air supply, supplying warm air to the home. Heat pumps are known for their convenience as an HVAC system that can both heat and cool a home in one unit. Air conditioners can only produce cold air, so they need to be paired with a furnace to create warm air in the winter. The air conditioner uses the furnace’s blower and the indoor cooling coil is housed in this cabinet, but the two systems operate separately.

Heat Pump vs Air Conditioner – Which Is Right for My Home?

Making the call on a heat pump and an air conditioner can be difficult, as both system types have some major similarities. Often, it comes down to the subtle but real differences found in a heat pump vs an air conditioner and how these elements apply to a homeowner’s situation.

Do You Need Heating and Cooling, or Just Cooling?

When deciding between a heat pump vs air conditioner debate is basically null when it comes to each system’s cooling abilities, as they function the same way. You can check out their SEER rating, or Seasonal Energy Efficiency Ratio, to see how efficiently specific units perform. The higher the SEER rating, the more efficient the cooling system. The heat pump efficiency when cooling a home is much better than central air conditioning systems. 

If you need a heating system for your home, a heat pump is your only choice for heat pump vs an air conditioner. The ability to reverse operation is what makes the heat pump so versatile—it can be used to cool or heat any space, whereas most other HVAC systems serve one function only. The heating efficiency of heat pumps is measured by HSPF, or Heating Seasonal Performance Factor. With mild winters in Kentucky, heat pumps typically offer highly efficient heating. However, when outdoor temperatures drop too low some heat pumps can struggle to be energy efficient. Many homeowners use heat pump systems most for cold air and pair their HVAC system with a gas furnace as a heating system. This is a smart solution for heating efficiency in the cold winter months. 

What’s Your Budget?

Overall, heat pumps tend to have higher installation costs. The indoor air handler is typically more affordable than a furnace, but the outdoor heat pump unit can cost more than an air conditioner. One of the major benefits of a heat pump is that it can also act as an air conditioner, so you don’t have to buy two separate units. If you need a solution for heating and cooling, purchasing a heat pump may be the more cost-effective choice. For cooling only, an air conditioner is more affordable.

HVAC Installation in Burlington, KY

If you’ve chosen a side in the heat pump vs air conditioner debate, it’s time for HVAC installation! Call Poston Brothers Heating & Cooling today and request an estimate for heat pump installation or air conditioning installation in your home.

The Importance of Indoor Air Quality

For most people, air quality issues evoke thoughts of smokestacks, smog and other outdoor air pollution. In reality, indoor air pollution issues have a much greater impact on homeowners’ health and comfort. Since the average American spends as much as 90% of their time indoors, reducing indoor air pollution helps you breathe easier. At Poston Brothers Heating & Cooling, we work with a number of homeowners and businesses to improve their indoor air quality. This is especially important for family members who experience seasonal allergies, respiratory discomfort or have asthmatic symptoms.

Your home should be an oasis from the elements. While most HVAC systems focus on regulating indoor air temperatures, indoor air quality is often neglected. Pollution has long been promoted as an outdoor issue, but more recently information has become available regarding indoor pollutant levels. According to the Environmental Protection Agency, indoor air inside a home or building can be two to five times more polluted than outdoor air. Improved indoor air quality can have a positive impact on your health and comfort.

Defining Indoor Air Quality

Indoor air quality (IAQ) refers to the presence of airborne particles considered contaminants, relative humidity, ventilation and temperature of the air within a space. Since there is a broad range of elements to consider, Poston Brothers always starts a consultation to test your HVAC system for efficiency. When your air conditioning, furnace and ductwork are working smoothly, we can focus our attention on optimizing humidity levels and reducing particulates from your indoor air.

Why Does Indoor Air Harbor More Pollution than Outdoor Air?

The most simple answer is volume and circulation. Outdoor air flows with the breeze and the weather which dilutes the concentration of many contaminants. Inside your home, there is far less air movement. Even the best ventilation system and most powerful air handler cannot circulate air constantly to disperse irritants at the same rate as outdoors.

Another factor is the quality of construction. Modern homes are designed to be extremely energy efficient. Building codes and other regulations help keep windows sealed, doors secure and attics well insulated. There are major improvements in how homes are heated and cooled. Energy efficiency helps reduce wasted energy but greatly impacts the air quality.

There needs to be a proper air exchange rate met to help get enough outdoor air inside and cycle the air carrying indoor air pollutants outside. Upgrading HVAC equipment improves indoor air quality. New air conditioning systems can filter more outdoor pollutants, and high-efficiency furnaces and air handlers capture more particulates than older models. Still, standard appliances only go so far.

What Are the Main Contributors to Poor Indoor Air Quality Problems?

While outdoor air pollution may infiltrate your home through the ventilation systems, the primary sources of indoor air quality issues are everyday products and activities.

Stoves and Ovens

Cooking contributes significantly to indoor air quality. This is quite surprising until you consider proper ventilation. During cold and hot months, homeowners are less likely to operate the hood. Exhaust from natural gas remains in indoor spaces.

Chemicals and Cleaners

Volatile organic compounds (VOCs) refer to chemicals that are emitted as gasses from certain solids and liquids. They are found in a wide variety of products, including paints, cleaning supplies, pesticides, and building materials such as flooring and furniture. High levels and constant exposure to VOCs can cause various health problems, including eye, nose, and throat irritation, headaches, dizziness, and allergic reactions.

Air fresheners, household cleaners and even personal products can impact the indoor air quality as well. The importance of indoor air quality really comes into play when we discuss exposure. Exposure to indoor air pollution is what puts people at risk for health symptoms and issues. Those of us who are most susceptible to health issues caused by exposure to certain airborne contaminants are more likely to spend an even greater portion of time indoors.

Mold and Biological Contaminants

Mold describes a common fungus that grows in damp or humid environments. It can grow on a variety of surfaces, including walls, ceilings, and floors. Mold can even form inside air ducts and on indoor vents. Mold produces spores, which are tiny, lightweight cells that can travel through the air and be inhaled into the lungs.

Exposure to mold can cause a variety of health problems, including allergic reactions such as sneezing, runny nose, and red or watery eyes. In some cases, mold exposure can also lead to more serious health problems, such as asthma attacks or other respiratory problems. In addition to mold, other common biological contaminants found in homes include bacteria, viruses, and allergens from dust mites, pet dander, and pollen.

When these allergens build up inside a home, they expose allergy and asthma sufferers to more of their triggers so they are more likely to suffer symptoms. Even in healthy people, exposure to high indoor air pollutants can lead to health side effects like runny noses, headaches, fatigue, and more.


Combustion of natural gas and propane creates emissions. A well-maintained furnace that is inspected annually will be tested for carbon monoxide. Cracks in heat exchangers, breaks in gas lines and damaged exhaust flues may result in harmful carbon monoxide buildup. Inspections reduce serious health risks, but there are other side effects. Beyond pollution, furnaces contribute to reducing the relative humidity levels in the air. Winter air is already dry, and combustion results in lower water vapor within your indoor air.

Other sources

There are some more obvious sources of indoor air quality issues including fireplaces, pesticides, radon gas and secondhand smoke. All of these contribute to reducing indoor air quality in some manner. Poston Brothers uses indoor air quality monitors like radon detectors, carbon monoxide detectors and carbon dioxide monitors to protect your family against these serious health risks.

HVAC Systems Improve Indoor Air Quality

Generally, maintenance, inspections and professional repairs will improve indoor air quality. Part of any professional HVAC system inspection is cleaning units, replacing air filters and checking ductwork for signs of leaks and damage. When homeowners form a relationship with a professional HVAC contractor, the maintenance occurs in the spring for air conditioning and again in the fall for furnaces.

Between professional inspections, there are a number of chores every homeowner can do to improve indoor air quality using their central air conditioning systems and furnaces. Regular cleaning reduces dust on surfaces. Often overlooked is frequently cleaning air vents. Check air filters monthly and replace dirty filters. Clean around furnaces and air conditioners to reduce outdoor contaminants.

There are additional services and products that improve poor indoor air quality. Duct cleaning services can help to restore your HVAC system. The greatest impacts are made by adding whole house equipment, including:

Air Cleaners

Air conditioners help to prevent outdoor contaminants from entering your home. Standard air filters also capture around 80% of airborne particles. Air cleaners have much higher MERV ratings, removing as much as 95% of airborne debris, allergens and irritants. Cleaner air reduces dust on surfaces and irritants in the air.

Air Purifiers

Air purifiers treat all the air circulating throughout your HVAC system with ultraviolet light. When viruses and bacteria are isolated within the air purifier, your overall immune health can be improved.

Humidifiers and Dehumidifiers

A major factor that is often ignored in indoor air quality is humidity. Controlling the ideal relative humidity levels in your home is important for reducing the risk of mold and other biological contaminants. Dehumidifiers lower humidity in risky areas like basements during high-humidity seasons.

Proper humidity levels also hold dust and debris within the air. This means that contaminates are captured in air filters and air cleaners instead of resting on surfaces. Dry air is a major irritant during winter weather. We have all experienced dry noses, itchy eyes and scratchy skin related to dry winter air. Improving indoor air quality by balancing humidity levels helps the air feel more comfortable. Humid air feels warmer and more comfortable which means thermostats can be set lower to save energy consumption.

Fight Seasonal Allergies with Good Indoor Air Quality

People who have asthma or suffer from allergies are no strangers to the importance of good indoor air quality. The amount of indoor air quality pollutants found in the air inside your home has a real and noticeable impact on the way they feel.

Seasonal allergies are common in a large portion of the population, especially in the spring. Pollen counts spike this time of year as trees and grasses bloom. Mold spores can exist in high volumes over the spring months, too. Even though these contaminants originate outside, the outdoor air coming indoors can easily increase indoor pollutant levels for people who suffer from these allergies. The pollutants make their way into homes through open doors and windows, on our shoes and clothing, and even on our pets. Once they come inside, poor ventilation keeps them trapped inside, and over time quantities continue to build. This can greatly increase indoor pollutant levels inside the home and can make allergy sufferers feel awful.

Reducing the number of indoor air pollutants and focusing on trying to improve indoor air quality in the home can help lessen your spring allergy symptoms. The right tools can help you remove these particles from the indoor air supply and fill your living spaces with fresh air so your symptoms decrease.

Gain Better Indoor Air Quality Through HVAC Solutions

Your HVAC system and the tools that work with it are key when it comes to the importance of indoor air quality. Improving ventilation by adding mechanical solutions can push out polluted air and fill your home with fresh air throughout the day. Indoor air quality equipment like air cleaners and air purifiers remove particles or neutralize organic contaminants so exposure is reduced.

Poston Brothers Heating & Cooling knows the importance of indoor air quality and how it can impact your health this season. Contact us today to learn more about the installation of indoor air quality equipment that will reduce indoor contaminants for a healthier indoor environment.