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How to Prevent Mold in HVAC Systems

Warm and cool air moving through your heating and cooling system can cause moisture to condense inside the system. Proper filtration, good airflow, and condensate drainage alleviate the risk of mold growth. However, even minor problems could disrupt the balance and create an environment for mold growth. For this reason, it is important that you know how to prevent mold in HVAC systems. As a homeowner, you can manage basic upkeep that keeps your heating and cooling system in a healthy state.

Tools Required How to Prevent Mold in HVAC Systems

  • Flashlight
  • Screwdrivers, if needed to open access panels
  • Wire hanger
  • Wet/dry vacuum

Signs of Mold in Your Air Ducts

Because mold problems begin in places that you can’t see, the problem can creep up on you. An unpleasant musty odor could be your first warning sign. At the same time, you might discover inexplicable moisture in areas of your house. You might also see black dust near the air vents.

The mold growth releases spores that travel through the air that you’re breathing. This can produce numerous health problems, including:

  • Headaches
  • Nausea
  • Itchy eyes
  • Coughing
  • Dripping nose
  • Difficulty breathing

Any of these signs and symptoms warrant contacting Oliver for duct cleaning. You need to get the mold out of the air system. After that, the causes of the mold growth can be remedied so that you prevent future outbreaks.

Step by Step How to Prevent Mold in HVAC Systems

  1. Replace the air filter monthly. A dirty, clogged filter impedes airflow. This allows dust to accumulate in ducts and potentially become damp. Moist dirt is a great medium for mold to grow in.
  2. To replace the filter, slide open the housing on the slot that contains the filter.
  3. Take note of the size of the existing filter.
  4. Buy a new filter of the same size and find the airflow direction arrow on its side.
  5. Insert the new filter with the arrow aligned with the direction that air moves through the ducts.
  6. Inspect the condensate pan and drain for leaks or clogs. The condensate pan collects moisture that forms as the system heats or cools air. A broken pan or clogged drain will get moldy and infect the system.
  7. Run the AC for about half an hour.
  8. As it runs, watch for water drips or pools around the unit or air handler.
  9. Shut off the AC at the thermostat.
  10. Shut off power to the HVAC system. It should have a dedicated circuit that you can shut down without denying power to the whole house.
  11. Unscrew or pry off the access panel near the evaporator coil which will be above the pan.
  12. Look at the pan to see if it is full of water or even covered with mold.
  13. A pan full of water means that it is clogged. It should be wet, but water should be flowing out the drain.
  14. Find the pan’s drain opening and slide a stiff wire through it to break through the clog.
  15. After the water drains away, slowly pour water onto the pan.
  16. Observe the pan for leaks. If it drains properly, clean the pan with an HVAC disinfectant cleaner.
  17. If the pan has leaks, call Oliver to replace the pan.
  18. If the pan is in good order, but the condensate drain line backs up, unscrew the cap of the cleanout tee.
  19. You might be able to break free the clog in the line with a wire or suck it free with a wet/dry vac. Otherwise, call us for professional AC maintenance.
  20. Test the line by pouring water through the pan and drain. If it is working now, put the cleanout tee cap back on.
  21. Check your HVAC air intakes and remove any items blocking them. This step ensures good airflow that helps keep the system dry and prevent mold growth.
  22. Have your ducts professionally cleaned. Removal of dirt buildup robs mold spores of a place to grow.
  23. After cleaning, mold prevention products may be applied to the ducts.

If You Find Mold You May Need Professional Service

Frequent filter replacement, unblocked intakes, and proper drainage should prevent mold. However, if something goes wrong and mold forms, you need systemic service. The technicians at Oliver can clean everything and repair the source of the problem. Elimination of mold is vital for your health and the future value of your home. Contact us at Oliver today for help.

Need help with this project?

If you do not have the time, tools, or experience necessary to complete the project, please contact the professionals at Oliver for help.

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