We mean this in the literal sense. Many people have a heating and cooling system that smells bad and this is even known as “dirty sock syndrome”. This pervasive odor can be hard to pinpoint initially and it’s often attributed to the trash, garbage disposal, and other possible sources of bad smells. If you’ve eliminated these possibilities, it may be time to take a good hard look at your HVAC system. In this article, we will take a closer look at the cause of this phenomenon and how you can remove this bad odor from your home.

What is Dirty Sock Syndrome?

When we visit a gym or go for a run, we tend to have dirty clothes and socks after we finish exercising. These clothing items often smell bad, but have you ever wondered why this is the case? The source of these bad odors is the bacteria that lingers in the clothing materials and it only gets worse as time passes. If the clothing items are not washed, they may even have mold and mildew growing on them. The foul odor will become worse and it seems to be noticeable throughout the home.

What Has This Got to Do with My HVAC System?

The HVAC system is also prone to the growth of bacteria, mold, and mildew. In fact, it would be fair to say that the system is pretty much an ideal place for them to thrive if there is any moisture present. These contaminants can grow in the evaporator coils or even in the ductwork. These locations may have excess moisture, they are dark, temperature controlled, and a likely spot for bacterial and mold growth.

Like all organisms, bacteria and mold require a food source and dirt and dust on HVAC components are edible for them. So, you may notice that the dirty sock odor is more noticeable in summer and winter when the HVAC system is working hard. The circulated air will contain bacteria and mold spores that will lower the indoor air quality (IAQ).

If your system has a heat pump, it is especially vulnerable to the formation of mold spores. In a gas furnace, the generated heat tends to be too intense for bacteria and mildew and they are often destroyed before they gain access to the home. An AC system is at risk of contamination because no heat is generated to kill these microorganisms and mold spores. Although this phenomenon is known as “dirty sock syndrome” the air may smell musty or dirty.

What are the Health Risks?

The short answer is no, but it would be hard to categorize it as healthy. Although our health is not at an immediate risk from bad IAQ, there are negative consequences after prolonged exposure. The EPA has estimated that we spend around 90% of our lives indoors which is unhealthy. When we think about pollution we tend to think about smog and car exhaust emissions. But, the IAQ can often be worse indoors than it is outside and the growth of bacteria and mold will only exacerbate the situation. In many homes, the levels of pollution indoors are almost 5x higher than the air outside!

When it comes to poor IAQ the first people to notice a problem are young kids, elderly people, allergy sufferers, people with compromised immune systems, asthma sufferers, and people with pre-existing respiratory ailments. These at risks groups will benefit from any improvements to IAQ if the core issue is addressed.

How Can I Remove the Bad Smell?

The bad smells are less noticeable in spring and fall when the HVAC system is not in regular use. But, the odor never really goes away unless the problem is fixed. As you can imagine, this will involve cleaning to remove the bacteria and mold. Although it may be tempting to clean the system yourself this is a bad idea. Removing the cover on the outdoor unit and scrubbing the evaporator coils can cause damage. Some of the components in the system are expensive to replace and it makes good sense to protect your investment. Scraping away some dirt and gunk may help, but this may not get all the bacteria and mold in the system.

If the problem lies deep in the ductwork, you will need some duct cleaning to sanitize the ducts. If the problem is in an advanced stage, it may even be necessary to replace the evaporator coil. This is why it’s a good idea to deal with this problem earlier to lower the costs. If your system is still under warranty it may be possible to reduce the repair costs if you can prove that you’ve not been negligent with the maintenance requirements. So, the best way to deal with dirty sock syndrome is to contact your local HVAC specialist to investigate the cause and fix it for you.

Regular Air Filter Changes

One easy HVAC maintenance task that anyone can perform is a filter change. This can prevent a wide variety of problems including bacteria, mold, and mildew growth. More pollutants can be captured if you use a denser filter but these will lower the airflow. If you’re unsure about which air filter you should be using, check your owner’s manual.

Schedule Ductwork Cleaning

The air in your home circulates through the HVAC system multiple times each day. Many contaminants are captured by the air filter, but some can enter the ductwork, and if there is any moisture present bacteria and mold growth can occur. So, it’s a good idea to schedule some ductwork cleaning to sanitize these spaces which will improve the IAQ too.

The Importance of Preventative Maintenance

The best way to deal with dirty sock syndrome and a wide variety of other HVAC problems is to invest in preventative maintenance. Sadly, many homeowners don’t think about their expensive heating and cooling systems until something goes wrong. When a problem is ignored, it tends to get worse as time passes and as a result, the repair bills tend to be higher. In more extreme cases, this can lead to component and system failures that are expensive. The best way to deal with these issues is to adopt a proactive mindset and schedule some essential maintenance for your HVAC system.