Reston has a mild, sunny week ahead. Highs will be near 70°F on Tuesday, with partly cloudy days in the upper 60s to low 70s after that, and cool nights in the mid-40s to near 50°F. With the heating season starting and nights turning cool, this mild stretch is a good time for one simple job: check your furnace air filter.
Your air filter traps dust and other airborne particles as air moves through your heating system and back into your rooms. How much it catches depends on the filter type. Over time, the filter fills up. A clogged filter can restrict airflow, so some rooms may feel cooler than others and the system may run longer than it should. A dirty filter is one possible cause of uneven heating, and checking it is a simple first step.
For most systems, checking the filter takes only a few minutes, and you do not need any special tools.
Here are the steps to check your furnace filter:
- Turn the system off. Set the thermostat so the heat is off, and wait until the blower stops before you open the filter slot or return grille. Follow your system’s instructions — if the filter is not safely accessible, or you are not sure how to reach it, have a professional do it instead.
- Locate the filter using your system’s manual or markings, and slide it out only if it is safely accessible. Note the size printed on its frame — and check your system’s instructions for the filter type you need — before buying the new one.
- Hold it up to the light. If little or no light passes through, or it looks grey, dusty, or matted — or it is simply due by the maker’s schedule — it is time to replace it.
- Fit the new filter the right way. Most filters have an arrow on the frame. Point the arrow in the direction the air flows, following the markings on the filter and your system’s instructions. If you are unsure which way the air flows, ask an HVAC professional.
- Write the date on the frame. This makes it easy to remember when you changed it. Check the filter once a month during heating season as a starting point, and follow the manufacturer’s recommended schedule for your filter — some need attention more or less often.
When a clean filter is not enough
If your home does not reach the temperature you set, you notice unusual noises, or rooms still heat unevenly with a clean filter, the cause may be more than the filter — and it is better to have it checked while the weather is still mild.
911Air-Care serves Reston and Northern Virginia, Monday to Saturday from 8 AM to 7 PM, with 24/7 emergency help. If rooms heat unevenly or your home will not reach the set temperature, we can check your heating system and filter together. Getting it done now helps you get ready for the colder weeks ahead.
