Maintaining your heating and cooling system’s air filters ensures optimal HVAC performance and is essential for indoor air quality. Failing to replace them when needed is a mistake many homeowners make. This article will explain why and what issues you’ll encounter if the air filter in your HVAC system is too dirty.
Poor Performance and Decreased Energy Efficiency
Failing to replace an air filter regularly affects HVAC energy efficiency and how much it costs to heat and cool your home. When your AC or heating is on, the blower continually pulls air in through the return vents. This air flows through the filter, which has tiny holes or perforations that allow air to pass through but trap airborne particles like dust, pollen, dust mites, and pet dander. The issue is that these particles continue to block more and more of the holes, resulting in the filter clogging up over time. This results in the system being unable to draw nearly as much air through the filter during operation.
When a clogged filter restricts airflow, your HVAC system cannot heat or cool your home as well or as quickly as it should. That means instead of your AC or heating running for around 15-20 minutes per cycle, it can take much longer before your home reaches your desired temperature. The U.S. Department of Energy suggests that a dirty filter can increase a household’s energy consumption by up to 15%. If your HVAC system isn’t performing as well as it should, it will run more each day and consume more energy, leading to higher utility bills
Increased Repairs and Shorter Lifespan
Another crucial reason to change the air filter regularly is that it significantly impacts the lifespan of your HVAC system and the frequency of necessary repairs. Air filters capture debris that could harm critical parts of heating and cooling systems. Additionally, dirty filters can allow dust to accumulate on internal components, potentially causing damage and reducing efficiency.
The increased strain on the system from the lack of airflow also leads to more wear and tear, shortening its lifespan. Regularly checking and replacing the filter, along with scheduling an annual heating and cooling tune-up, can save you money by reducing repair costs and extending the life of your HVAC system.
Poor Indoor Air Quality
While an HVAC system’s air filter’s primary purpose is to protect the internal components of heating and cooling systems, it is also critical to maintaining indoor air quality. It captures airborne pollutants that would otherwise recirculate throughout your living spaces. Good filter maintenance reduces the amount of these contaminants that your family breathes in while relaxing at home.
Frozen Air Conditioner
Another situation you’ll often run into when the air filter gets too dirty is that your air conditioning will start having issues where the evaporator coil freezes up. The evaporator coil is what allows the refrigerant in an AC system to capture heat. It also helps with humidity control since moisture in the air condenses on the cold coil once the air temperature decreases to its dew point. A central air conditioning system can remove up to 20 gallons of water from your home’s air on sultry summer days.
Although the evaporator coil is extremely cold, the warm air flowing over it normally prevents the condensation from freezing. The problem is that when the filter is too dirty, you’ll end up with far less warm air getting drawn into the AC system and blowing over the coil. The result is that the condensation can quickly start to freeze leading to ice building up on the coil. Once this happens, your air conditioning won’t work since the ice blocks the coil and prevents the refrigerant from absorbing heat.
In this situation, shutting your air conditioning off is important, or you risk damaging the compressor in the outdoor unit. You will then typically need to wait a few hours for the ice to melt before turning your AC back on. In the meantime, you should check and replace the filter. Lack of airflow is the most common reason that cooling systems freeze up. However, if the issue continues, you should have a professional inspect your system. Your air conditioner could have a refrigerant leak, a malfunctioning blower fan, or another problem needing an expert’s attention.
Overheating
When the air filter of your central air conditioner or heater is dirty, the blower must work harder to draw air into your HVAC system. This may cause it to overheat and shut down. It also may cause damage to the motor, which will eventually result in the need for an expensive replacement.
A dirty filter can also lead to insufficient cool air entering your furnace in winter, causing it to overheat. Modern furnaces have a limit switch that shuts down the unit if the heat exchanger gets too hot to prevent a fire hazard. However, if your furnace is often running at a temperature higher than it is designed to handle due to poor filter maintenance, it can cause significant damage. Various electrical components, such as the control board, wiring, and safety switches, can fail due to excessive heat.
Additionally, if the heat exchanger overheats and cracks as it cools, you will most likely need to replace the entire furnace. The heat exchanger is a critical component of your system, responsible for heating the air that is circulated throughout your home. When it cracks, it presents a risk of releasing carbon monoxide into your living spaces, which can make family members ill or even be fatal. Repairing a cracked heat exchanger is often not feasible or cost-effective because the labor and parts costs can approach or exceed the expense of installing a new furnace.
You Should Replace HVAC Filters At Least Every Three Months
Experts recommend replacing the air filter in your heating or cooling system at least every three months. However, you may have to change them out more often than recommended. Several factors can influence how quickly filters become clogged, such as how many people live in your household, if you have pets, and if your system runs more often during a cold snap or heatwave. You will also have to replace them more often if you use more efficient filters with a higher rating to improve your home’s indoor air quality. Higher-quality filters capture more airborne contaminants and become clogged faster. Many homeowners inspect their filters once a month to ensure they know when they need to be changed out.
Contact the Professionals
With over 20 years of professional experience, Green Dot Heating & Air is the company residents in the Wilmington area can trust for all of their air conditioning, heating and indoor air quality needs. We offer expert AC maintenance, repair, and installation services, and our technicians have the knowledge and skills to ensure your HVAC system always works as it should. Contact us today to schedule an appointment with one of our experienced team members.
