With spring finally here, we can look forward to longer days, steadily increasing temperatures and, unfortunately, a huge amount of tree pollen in the air. Pollen is obviously a concern for allergy sufferers, as it causes unpleasant symptoms like coughing, wheezing, sneezing and eye irritation. What you may not realize is that tree pollen also negatively impacts your outdoor HVAC unit and can lead to your energy bills spiking long before the summer heat and humidity arrive. In this article, we’ll look at the issues pollen creates for an HVAC system and what steps you can take to lessen its impact.
How Tree Pollen Affects Outdoor HVAC Units
Oaks, pines and other non-flowering trees rely on the wind for pollination. For wind pollination to be effective, the male trees have to continually release massive amounts of sticky pollen into the air so that at least some of it reaches nearby female trees. Oak trees are especially prolific when it comes to pollen production, as each of the individual catkins releases millions of grains of pollen every year.
Tree pollen is fairly sticky, which is why you often see a layer of it on vehicles. Just as it sticks to your car, it also gets inside your outdoor HVAC unit and coats the various components, including the condenser coil.
Pollen on the condenser coil is problematic for several reasons. One is that it insulates the copper tubes, resulting in the air the fan draws into the unit not directly contacting the metal. Even worse is that it clogs the metal fins, almost completely blocking air from reaching the coil.
The condenser coil plays an extremely important role in the heat transfer process your HVAC system uses to cool your house. The refrigerant absorbs heat from the air flowing through the HVAC system as it circulates through the evaporator coil inside the house. This heat is then released into the outdoor air as the refrigerant circulates through the condenser coil. However, this process only works effectively if there is sufficient air flowing through the fins and across the copper tubes, which can’t happen when everything is coated with large amounts of pollen. Now that you understand the basics of how pollen impacts your outdoor HVAC unit, we’ll discuss the specific issues it creates.
Decreased Cooling Performance
When the condenser coil is clogged with pollen, your HVAC system can’t cool as effectively because the pollen prevents as much heat from flowing out of the refrigerant into the air. That means the refrigerant doesn’t get as cold as it normally should by the time it exits the coil and gets pumped back inside the house. Refrigerant can only hold so much heat. If it’s warmer when it circulates through the evaporator coil, it can’t remove as much heat from the air flowing through the air handler. The result is that the air doesn’t get cooled off as much before exiting the air handler and then getting circulated around the house.
Under normal conditions, an HVAC system should decrease the temperature of the incoming air by around 15 to 20 degrees. If the refrigerant is warmer because the condenser coil is dirty and clogged, you may only get a temperature drop of around 10 degrees or so. That means the system may need to run almost twice as long to cool the house to your desired temperature.
Reduced Energy Efficiency
Cooling performance and energy efficiency go hand in hand. If your HVAC system isn’t performing as effectively and takes longer to cool your house, it will obviously use more energy. Depending on how dirty and clogged the condenser coil is, you could see anywhere from a 5% to a 30% decrease in energy efficiency. If you don’t get a handle on the problem before the extreme Texas heat and humidity arrive, even a 10% decrease in efficiency can cost you a significant amount of money.
Increased Wear and Tear
The other concern when your HVAC system isn’t performing as effectively and has to run more is that it leads to increased wear and tear on all of the components. This creates the potential for the system to suddenly break down due to a component like the fan motor or blower motor wearing out and failing. The more wear and tear the system experiences, the sooner you will likely need to replace it as well.
How to Lessen the Impact of Pollen on Your HVAC System
While there’s nothing you can do to keep pollen from getting inside your outdoor HVAC unit, there are some basic steps that help to avoid it from causing major issues. When the trees are in bloom and the pollen level is higher, it helps to rinse the unit with a hose every few days or at least once a week to wash away the pollen. Rinsing the unit with water is completely safe, as long as you’re gentle and use a hose, not a pressure washer.
The most important thing to do is to schedule a tune-up with a licensed HVAC company in the spring, preferably after most of the trees have released their pollen. Part of a tune-up service is cleaning the condenser coil. Washing the coil with a hose helps to cut down on pollen, but professional coil cleaning is much more thorough and much more effective. During the tune-up, the technician will also inspect and test everything to make sure that there aren’t any issues that contribute to decreased efficiency or could lead to the system breaking down over the summer.
Oak pollen isn’t the only concern in spring. If there are any cottonwoods or other poplar trees in your neighborhood, the cottony seed fluff that their catkins produce will often get trapped within the grilles on the side of your outdoor HVAC unit. The fan draws air in through the sides of the unit. If the grilles are clogged with debris, the fan can’t pull in nearly as much air. This again prevents the refrigerant from releasing all of the stored heat, resulting in the same performance and efficiency issues that occur when the condenser coil is dirty and clogged with pollen.
Luckily, you can easily prevent and overcome this problem by regularly checking the unit once you start seeing the trees releasing their seeds. If it starts collecting within the sides of the unit, you can usually remove it fairly easily with a shop vacuum or even just by using a broom or brush.
Get Your System Ready to Help You Brave the Heat of Summer
If you want to make sure that your HVAC system is fully ready for summer, the experienced professionals at Rosenberg Plumbing & Air are ready to help. We’ve been providing reliable AC maintenance to homeowners in San Antonio and the surrounding areas for more than a decade and will make sure your system is in tip-top shape. Enrolling in our Comfort Club Membership is the best way to ensure your HVAC maintenance needs are properly taken care of. Plan members receive a yearly cooling tune-up and a yearly heating tune-up as well as additional benefits like priority scheduling, discounted repairs and reduced service fees. To schedule a tune-up or learn more about our maintenance membership, contact us today.
Tags: AC Maintenance