The air handler draws air out of the house through the return duct system and then blows the air through the heating or cooling system and returns it back to the house via the ducting system. The air cleaner is normally located at the point where the return duct enters the air handler. In most homes, you'll find the air filter housing situated right next to the air handler of your heating or cooling system. This is a large metal box with a fan motor and a fan inside. In many cases, the air handler is installed in the basement, attic or utility closet.
It's likely that your heating and cooling system is where you'll find your air filter. If you're not sure where your air handler is located, check the attic, basement, mezzanine or garage. If you live in a smaller space (such as an apartment), your unit is likely to be in a closet. The next step can be more complicated to find the air filter. It may be difficult to locate in some HVAC systems, but you can usually find it in the return air duct.
Or in simpler terms, that big metal grille on the wall, floor, ceiling or door of the utility closet. Return air ducts can be virtually anywhere. Some larger homes have more than one air conditioning system, and each will have at least one filter. Take a look first at the filters inside or near the HVAC unit itself. It's very likely that these filters are located next to the oven or the air conditioning controller.
The HVAC unit can often be found in an attic, basement or in the back of a closet (somewhere out of sight).Once you have found the unit, look for a hinged or removable cover about an inch wide. It can be oriented horizontally or vertically, and you should find a filter already in place. The air filter is usually near your home thermostat in a return duct. Or, it's most likely right next to the air handler of your air conditioning system. It's usually located in the return air duct or in the fan compartment before the return air reaches the air handler.
By the 1940s, oil bath designs had replaced water bath designs due to better filtering performance. But it's not certain if the air handler itself can have a separate filter that also needs to be changed every season; the orifice unit is only 4 years old. Replacing your home's air conditioning filter will allow it to continue blowing cold air without interruption. In fact, as long as a pleated paper filter is sized appropriately for the volumes of air flow encountered in a particular application, such filters only present a trivial restriction to flow until they are significantly clogged with dirt. If it's a window air conditioning unit, you should clean the coils on the front of it, just behind the filter.
I saw grill panels with cables and tubes, but nothing that seems to belong to a filter function. Such cleaners are still used in off-road equipment where very high levels of dust are found, since oil-bath air purifiers can sequester a large amount of dirt relative to their overall size without loss of filtration efficiency or airflow. All central heating and cooling systems must have an air filter, but it may be more difficult to locate them in some HVAC units than others. Oil-moistened polyurethane foam elements are used in some car replacement air filters. These can be a good option for filtering a house if one of its residents has a respiratory disorder or allergy. In past times, foam was widely used in small engine air filters of lawn mowers and other electrical equipment, but automotive-type paper filter elements have largely replaced oil-moistened foam in these applications. In vertical air handling units with the return air duct entering through the top of the air conditioning handling unit, you'll often find that the filter slides into a slot above it.
