It’s no secret to any homeowner with an HVAC system—it needs to be kept clean. The most recognizable way to do so is by regularly changing air filters in the system. There are many different air filters from which to choose, so sometimes it can be difficult to know which filters to buy. Many systems manuals will give the minimum requirements for these filters, both in type and regularity of which to change them out. Sometimes, however, there are better solutions that those initially recommended in these products manuals.
An air filter, regardless of type, should be checked every month or so to see how dirty it is, especially during heavy use months. Standard filters usually should be replaced within three months, but there are some advanced HVAC filters that can last longer. Replacement of the air filter is typically the first defense against a dirty HVAC and duct system. A dirty filter will slow down airflow and make the system work harder to keep you warm or cool — wasting energy. A clean filter will also prevent dust and dirt from building up in the system — leading to expensive maintenance and/or early system failure.
Unfortunately, sometimes even regularly replaced air filters can’t defend completely against the home’s HVAC system and equipment from getting dirty. It’s possible that there are leaks or cracks in the system near the fan unit, causing dirtier air to bypass the filter altogether and get into the system over, which can lead to dirt and dust buildup in the unit’s machinery over time. This can especially be the case with a dirtier filter. If it is hard for air to get through that filter, it will get into the system one way or another (with the system working extra hard, of course). Air typically follows the path of least resistance, so when that path is no longer through a dirty filter, it will find another way.
Another possibility for unfiltered air getting into the system is a poor filter rack design. HVAC air filters can be top of the market and extremely effective, but without a good rack design to house them they can be rendered somewhat useless. This is a point of frustration for both the homeowner who is regularly purchasing high quality filters and for technicians and contractors who have to clean or do maintenance on these systems. In a poorly designed or damaged filter rack system, air can bypass the filter through any loose-fitting connection or crack. This dirty air is not only soils the equipment, but can also be dispersed throughout the household via the ducts. This can have a very negative effect on the overall indoor air quality of the home.
Improper air filter size can also play a large role in ineffective filtering. It’s imperative that you’re not only paying attention to the filter type you’re purchasing for your unit, but also the size of the filter itself. The filter “size” is measured in filter velocity (typically ranging from 200-400 depending on your HVAC unit). Your system manual will inform you which you need to install for top performance and for keeping your HVAC unit clean.
If the inside of your system does become dirty, we can help. We offer full cleaning of the systems we sell and service as part of a comprehensive BelRed Comfort Guard Maintenance plan.
