A dirty air filter in your HVAC system is inevitable. After all, the entire air volume inside your home circulates through the filter multiple times each day when the A/C or furnace is running. However, a filter shouldn’t get too dirty, too soon. Generally, the air filter should only require replacement every month or two. If the filter appears dirty, dusty and clogged sooner than that, it’s a tip-off that some other issue may be impacting indoor air quality and affecting filter condition.
Here are some alternate reasons why a dirty air filter gets that way sooner than it ought to.
Shedding Pets
When dog and cat hair isn’t clinging to carpets or upholstery, it’s afloat in the air and soon sucked into HVAC return vents, then trapped by the air filter. Pet hair mats inside the filter, strangling airflow and accelerating dirt and dust accumulation. Vacuuming more often to remove pet hair before it becomes airborne is one way to keep the filter cleaner longer. With certain breeds, brushing more often (outdoors) can also help reduce shedding that ends up in the filter.
Fan Setting “On”
Your thermostat offers two fan setting options. In the “On” setting the fan runs non-stop, whether the A/C or furnace is cycled on or off. This continuous air circulation rapidly accelerates the particulate load captured by the filter, clogging it sooner. Choosing the “Auto” fan setting instead runs the fan only when the A/C or furnace actuates, reducing the load on the filter.
Wrong Filter Type
High-efficiency air filters are usually designed for applications such as medical facilities and/or HVAC systems that have been specially modified. Since the very thick filter media clogs more rapidly and requires frequent replacement, they are generally not suitable for residential use. For most homes, choose a pleated cotton or polyester filter with a MERV (Minimum Efficiency Rating Value) between 8 and 12 for good filtration and a standard one- to two-month replacement interval.
Does your dirty air filter require more frequent replacement than it ought to? Get a professional opinion from the experts at CCAC.
Our goal is to help educate our customers in Corpus Christi, Texas about energy and home comfort issues (specific to HVAC systems). For more information about your HVAC system, download our free Home Comfort Guide or call us at 361-678-2495.