If you are one of the millions of Houston and Central Texas residents who suffer from cedar fever, you already know that the season is relentless. Mountain cedar trees release enormous quantities of pollen between December and February, creating the most intense seasonal allergy event in the region. What most people do not realize is that your home’s HVAC system plays a significant role in how much cedar pollen you are actually exposed to indoors.
Understanding how cedar pollen enters your HVAC system, where it accumulates, and what you can do to reduce your indoor exposure during cedar season will help you protect your family’s comfort and health during the most challenging months of the year.
How Cedar Pollen Enters Your Home’s HVAC System
Cedar pollen is exceptionally fine — each grain measures approximately 25 microns in diameter. These particles are small enough to pass through most standard residential air filters and enter the interior of your ductwork, where they settle on the inner surfaces of your return ducts, on the evaporator coil, and inside the plenum box.
During peak cedar season, a single mature tree can release over one billion pollen grains in a single season. When your HVAC system pulls outdoor and indoor air through return vents, a significant portion of that pollen load enters the system and deposits on interior components. This pollen remains inside your ductwork long after the outdoor season ends, serving as a continuous allergen source.
Why Cedar Pollen Inside Your HVAC System Is a Year-Round Problem
The cedar pollen that enters your HVAC system during the winter months does not simply disappear when the season ends. It settles on interior duct surfaces, the evaporator coil, and the plenum box, where it becomes part of the organic debris layer that accumulates inside your system year-round.
When spring arrives and your HVAC system begins operating in cooling mode, the moist surface of the evaporator coil combines with the accumulated cedar pollen to create ideal conditions for mold growth. This means that cedar pollen that entered your system in December can contribute to mold colonization on your evaporator coil in May.
The combination of cedar pollen and mold produces a dual allergen load that is redistributed into your living spaces every time the system operates, extending the effective impact of cedar season well into the spring and summer months.
What You Can Do to Reduce Cedar Pollen Exposure Indoors
**Replace air filters frequently during cedar season.** During peak cedar season, replace your air filter every 20 to 30 days instead of the standard 30 to 60 day interval. Upgrading to a MERV 11 or MERV 13 filter captures more cedar pollen before it enters the interior of your duct system.
**Keep windows and doors closed during peak pollen hours.** Cedar pollen counts are highest on dry, windy days. Keeping your building envelope sealed during these periods reduces the amount of pollen that your HVAC system must handle.
**Schedule professional duct cleaning after cedar season.** Cleaning in late winter or early spring — immediately after the peak of cedar season — removes the heavy pollen accumulation before it can contribute to mold growth during the cooling season.
**Run your HVAC fan continuously during peak pollen days.** Running the fan continuously improves the filtration of indoor air, as the air passes through your filter more frequently.
When to Seek Professional Help
If cedar fever symptoms persist inside your home despite these measures, or if you notice musty odors, increased allergy symptoms, or visible debris around your vent registers after cedar season, professional assessment of your HVAC system is warranted. Our NADCA-certified technicians will document the condition of all 8 components and determine whether professional cleaning or mold remediation is needed.
Book Your Free Inspection
If cedar season is affecting your family’s quality of life inside your Houston home, schedule a free inspection today. Our technicians will assess the extent of pollen and biological contamination inside all 8 HVAC components and provide an honest recommendation.
[Book a Free Inspection](https://crm.ahchooindoorair.com/book)
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