Air conditioning filters are devices that keep dust and dirt from both clogging the air conditioning system and contaminating the air. In a building, the filter is usually inserted into the large air return duct. As air is pulled through the filter, dust and dirt are trapped in the fibers. A good filter can also be responsible for trapping allergens. All filters need to be cleaned or replaced regularly.
It is important to ensure air conditioning filters are clean and are the right size for the air conditioning unit. A filter that is too small or a filter that is dirty can have several adverse effects. Effects include raising the amount of power the unit consumes, reducing cooling or heating, and contributing to the unit’s failure. The right filter will help keep the air and the air conditioning system clean and functioning properly.
There are several types of air conditioning filters. The first type is the fiberglass filter. It is the cheapest and typically only traps large particles, leaving smaller particles to travel through the air. These filters are not made to be cleaned but instead must be replaced. It is important to make sure these filters are not in use while they are dirty because it may cause the system to overwork.
Pleated fiberglass air conditioning filters are more efficient at trapping dirt. The material it uses is more densely woven together. Thus as air passes through the fibers, more dust and dirt are able to be trapped. The surface of these filters is also pleated which increases the surface area. This means that a pleated filter will be able to trap more dust than a flat filter of the same size.
Permanent mesh air conditioning filters can be made from different types of material. As such, their effectiveness can vary. These filters, however, are washable. After washing, some must be sprayed with adhesive to trap dust and dirt. They may also need to be changed eventually because of wear and tear.
Electrostatic air conditioning filters are made from material that produces a charge when air passes through it. This charge attracts dirt and dust from the air and holds it to the surface until it can be washed off. Electric air conditioning filters are similar except it uses an electrical power source to do its work. It is composed of a pre-filter and a main filter that work together to filter the air. The pre-filter traps large particles, and the main filter traps smaller ones.
High-efficiency particulate arresting filters, or HEPA filters, are possibly the most effective filters. They are said to remove 99.97% of particles that have a diameter of 0.3 micrometers—smaller than the diameter of human hair. In this filter, the fibers are randomly arranged. It also contains pleats which increase surface area, making for a more effective air filtering system. HEPA filters are also used in vacuums and in hospital rooms.