Your HVAC system’s ability to heat or cool your home effectively depends on its ability to circulate air. The air filter protects this function, capturing airborne contaminants before they can enter your system. The downside to that job is that you must replace them periodically. Use this guide to learn how to tell when it’s time to change your filter.
Average Filter Life
Leaving your filter in place for too long reduces your system’s efficiency, increases your heating and cooling costs, and adds strain and wear to your system. That’s why it’s important to change the filter regularly. How often you need to change it depends on the depth of the filter.
Smaller 1- and 2-inch filters are the most common and generally need changing every 30 to 90 days. Larger 3- and 4-inch filters may last from six to nine months. Filters that are 5- or 6-inches could last up to 12 months. Your air quality, the filter construction, and how you use your system will determine how often you’ll need to change your filter.
Ideally, check your filter every month, especially if you’re not sure how quickly it becomes soiled. You can extend your filter life by gently vacuuming the intake side of the filter when you change it.
The Air Filter Looks Dirty or Clogged
When you check your filter, look for evidence that it’s dirty or clogged. The filter itself will often look gray or brown. It could also have a thick layer of dust or pet hair when it’s time for a change. If the dust and other contaminants fall off when you remove it from the system, it needs to be changed.
Longer Heating or Cooling Cycles
Standard air conditioners run cooling cycles of 10 to 15 minutes and furnaces run 15 to 20 minute heating cycles. However, when the system cannot circulate enough air, it may take longer to bring your home to the desired temperature. This can also signal other problems, but a severely clogged air filter is a common culprit.
Less Air from Supply Vents
You likely don’t have the equipment to measure the air volume coming from your vents. However, you might notice that there seems to be less cool or hot air coming from your supply vents. A dirty air filter can cause this because it restricts the air from moving past the filter as it comes into the system. Less air coming in translates to less air coming out. It’s this restricted air that causes so many of the other issues associated with dirty and clogged filters.
Increasing Energy Bills
Keep an eye on your energy bills, including those for electricity and heating fuel. While what you pay is important for your budget, the energy you consume is more telling for your HVAC system. There are a few ways to look at your bill to catch when your system experienced reduced efficiency.
The first is the amount you consume each month, which will fluctuate based on usage habits and outside weather. More meaningfully, check how much you consume compared to the same month last year, which is usually available on your bill. If it is markedly higher with no other explanation, an airflow restriction like a clogged filter could be the culprit.
Excess Household Dust
Every home has some dust that needs to be cleaned periodically. However, when the air filter gets clogged, you’ll notice more dust because the filter isn’t removing it to the degree that it should. Keep an eye on the flat surfaces around your home to watch for excess dust. With a clogged air filter, the place you’ll most likely see this excess dust is around and in your ducts. Therefore, keep an eye on the floor around supply vents, on the vent covers, and just inside the vents. If you do notice this extra dust, be sure to clean it up when you change your filters to prevent recirculating these particles through your home.
Unusual Odors
Your HVAC system shouldn’t produce odors when it’s running properly. However, when the filter clogs, it could produce some odors. The most common is musty or moldy odors, especially if you have pets. This happens because bacteria and other contaminants get caught in the filter, which may produce the gasses that cause the odor.
Further, a clogged air filter can cause a burning smell, especially during the winter when dust hits the hot surfaces. Don’t ignore any unusual odor produced by your HVAC system, which could indicate potentially serious and dangerous problems, but could be as simple as a filter needing changing.
Increasing Allergies
Dust, pollen, and pet dander are just a few of the allergens in your home’s air. Your air filter works to help clear these out while the air circulates through your HVAC system. However, when it gets clogged, fewer of those contaminants get removed from the air. Further, those contaminants collect in a concentrated area, which can cause anyone who comes near the filter to have exacerbated allergic reactions. Further, those concentrated contaminants can get drawn into the system if there’s an air leak around the filter. This can create a hyper-allergenic environment throughout your home. If you notice anyone in your home sneezing more, with extra watery eyes or a runny nose, check your air filter.
Overheating Furnace
As your furnace produces heat, insufficient air moving through the system may cause the system to overheat. You may notice this excess heat simply touching the furnace housing. However, you are more likely to notice overheating because your system is short-cycling and shutting off prematurely. Even if you’re not paying attention to the length of the heating cycles, you will likely notice that your home isn’t getting to the desired comfort level.
Water Around Your AC Unit
Your air conditioner condenses moisture in the air due to the temperature of the evaporator coils compared to the due point of the air. When the AC works properly, this moisture, called condensate, drains away through a special drain in the drip pan. However, when there’s a problem, this condensate may spill onto the floor around the unit.
A clogged air filter is one problem that can cause excess condensate. The restricted airflow through the filter can cause the condensate on the coil to freeze. This becomes a compounding problem as the freeze itself further limits airflow through the system. When the coil thaws, there may be too much condensate to effectively drain, and it will instead spill out of the drip pan.
When property owners around Kingman need HVAC service they can trust, they’ve turned to Air Control Home Services since 1990. Our team takes pride in providing heating and AC maintenance, installation, and repair alongside indoor air quality solutions and a wide range of residential plumbing and electrical services. Call to schedule seasonal HVAC maintenance with one of our experienced technicians to help ensure your system continues operating at peak efficiency.
