HVAC Mold Remediation Demystified: Expert Tips and Techniques

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Updated on:

September 20, 2023

Combatting HVAC Mold: A Comprehensive Guide to Remediation

Visible mold on your basement walls, carpet, or drywall is a problem. However, the presence of mold in HVAC (heating, ventilation, and air conditioning) systems poses a serious risk to you, everyone residing in your house, and even your pets. When your furnace or air conditioner runs, the fan turns on, and the airflow will spread mold spores throughout your entire home if your HVAC system has mold. Every room and area will be contaminated with mold spores. Your mold problem could get worse the longer the system is used while polluted.

In this article, we will provide a guide on how to remedy the havoc system mold growth in order to prevent any harm coming to you and your family. After conducting the cleaning, you will see how drastically the indoor air quality will improve.

Key Takeaways:

  • Mold in HVAC systems poses health risks and affects indoor air quality. Prompt action is crucial.
  • Signs of mold include visible mold, odors, and symptoms like headaches and itchy eyes.
  • DIY remediation requires PPE, cleaning solutions, steam for killing mold, and ozone for odor removal. Professional services are recommended for effective and safe cleaning.

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Table of Contents (Show)

Table of Contents (Hide)

Allergic reactions for mold

How to find out if you have mold in the HVAC system air ducts

Molds are typically easy to see. However, while they are invisible, you will notice their stench in the air or certain symptoms in family members or pets.

Most of the time, you can smell mold in air ducts or vents before you can see it because of the stench. As a result, if your heating and cooling units (if they share ducts) start to have a moldy or musty smell anytime you are not using your air conditioning unit, mold is likely growing in your HVAC system.

You can get mold inside your home ducts system if new home was not in use for a long period of time after construction.

Watch out for the apparent mold as it appears around AC vents, in ductwork, and in drip pans. Condenser coils are the ideal place for mold to grow since they draw moisture from the air and into drip pans. This is especially true if they become clogged.

Last but not least, mold in air ducts is one potential explanation when residents or animals start displaying symptoms including headaches, nausea, sore throat, and itchy eyes whenever the air conditioner is on.

Please not that mold exposure is very dangerous and can cause health issues like allergic reactions, runny nose, and other respiratory issues.

Learn more about complete mold cleaning out from car.
mold spores
Mold spores

Why does mold grow in the HVAC systems?

In ductwork, mold develops when there is moisture and a warm environment. Mold thrives best in warm, humid environments, and Houston, Texas is one of these locations where mold removal services may always be required.

An excessively big air conditioning unit that has improper sizing might create the surplus moisture that mold needs to thrive since larger units in compact rooms cool the air too quickly and turn off before dehumidifying it.

A leaking duct can encourage the growth of mold because leaks in certain ducts allow warm air to enter.

Additionally, if you regularly keep your air conditioner at a very low setting, you can be encouraging mold to grow in your HVAC system's ducts.

How to remediate mold in HVAC ducts

You must identify and stop the source of any extra moisture or water in the system before you can start remediation. The HVAC system must be turned off, which is the next crucial condition. You don't want a blower to start up unexpectedly while you're trying to clean up. A procedure for removing mold should always begin with the establishment of containment of the HVAC system. The last thing you want to do is to let any mold spores go into nearby rooms or places that aren't already afflicted.

There are many different kinds of chemicals and cleaners that can be used to remove mold. That being stated, attempting to complete this activity could be exceedingly challenging and perhaps dangerous. Professionals can remove mold from air ducts using a variety of mechanical cleaning tools such brushes, blowguns, air whips, steam cleaners and vacuums before pushing or pulling the mold into specialized collection devices. They are also knowledgeable about the kinds of antimicrobial or biocide agents that can be placed into an HVAC system without causing harm.

extremely dirty ducts

DIY remediation for duct cleaning

The vital first step for the do-it-yourselfer is personal protection equipment, or PPE. When removing mold, you must use gloves, safety goggles, and an N-95 grade mask to protect your personal safety.

Make sure the system is turned off once more. To ensure that the furnace or air conditioner won't turn on, turn off the relevant circuit breaker(s). Any furnace filters should be taken out, sealed in bags, and thrown away. Then, combine the required amount of water with a cleaning solution that contains baking soda, borax, or household detergent. (Or use 1 part borax with 16 parts water; use 1 teaspoon detergent with 1/2 cup baking soda and 1 cup water.) The answer ought to be put into a spray bottle.

Remove any observable mold with a HEPA (high efficiency particulate air) vacuum. Use the spray bottle to liberally apply your cleaning solution to the moldy spots, and then let it sit for a while. Wipe the areas where you noticed the mold with disposable towels. Repeat using the HEPA vacuum to clean the area. In some cases, especially if there was a lot of mold present, you would need to redo the entire procedure. Before putting the filthy towels in a trash can, don't forget to bag them.

Apply a mold inhibitor lastly to prevent the growth of mold inside your HVAC system. Use only EPA-registered goods that are designed for use with HVAC systems, and make sure they are. Remember that mold can start to grow in as little as 48 hours, so you should check your system again in a few days.

How to stop the mold contamination in the air vents and HVAC systems

Years of battling resistant molds have taught us one thing: mold can be controlled by controlling moisture. Destructive mold infestations should therefore be avoided by controlling moisture.

The following advice will help you stop mold from growing in your HVAC system:

  • Regularly swap out your HVAC filters, clean coils.
  • To help prevent condensation, insulate air ducts.
  • Examine and clean your drop and condensate pans.
  • If you discover leaks, take immediate action to stop moisture buildup.
If you want to deep more in mold and mildew removal from your home learn more in this guide.
Learn more in this guide about mold smell removal out of car.

Questions & Answers

What is the biggest factor that causes mold spores?

Excess moisture is one of the biggest factors that produces mold in your HVAC. The warmer seasons make the perfect environment for mold to grow due to humidity, this is why it is important to check your AC unit during this season.

Mold removal professional
Mold removal professional

When should I call an HVAC professional?

We would recommend calling a professional company the second you find out you have mold. It is better to clean the HVAC system yourself for maintenance. It could be very tedious work to do a HVAC mold remediation by yourself, but if you have a lot of time on your hands, it is possible cleaning mold yourself.

About the Authors

Koren Zitser
Vip Air, Panama: 20+ years in global AC excellence. Partners with industry leaders, offers split to large-scale systems, specializing in VRF, Multi V, maintenance, and innovation.
Kristina Tretyakova
Distinguished as a South Florida Top-10 student in 2021. Studying Marketing and Business Administration at FIU. Proficient in daily operations and skilled in cleaning, auto detailing and copywriting.

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