With the exception of a few temperate days in the spring and fall, HVAC (heating, ventilation and air conditioning) systems tend to run all year. Preventative maintenance is needed to ensure HVAC systems perform at optimal levels. Without maintenance, systems may fail when needed the most. Although conducting preventative maintenance is an expense, spending a little regularly to keep the HVAC system running smooth will prevent big expenses later if the system fails and requires replacement.
Replacing filters is the simplest preventative maintenance measure and also leads to better performance. Heating and air conditioners circulate air back into systems to alter temperature levels. Air must be filtered before it can enter a heat exchanger or go over cooling coils. The filter picks up dust and debris and becomes clogged with use. Replacing the filter results in a clean air flow and reduced work for the intake to pull the air from the interior.
Usually, the filter is located behind a grate or inside a slot in the air vent. Open the access panel, slide out the old filter and slide in a new one. During extreme weather periods, the filter should be replaced at least monthly. Ensure the replacement filter is the correct type for the system. Filters too small or improperly shaped can allow dirty air to enter the system. Filters that are too large and jammed into place can inhibit airflow and reduce the system’s ability to control the temperature.
The air conditioner compressor lowers the pressure inside the system, thereby lowering the temperature of the coolant. The coolant is a gas that is compressed into a liquid and then expands back into a gas as it extracts heat from the surrounding air. The coolant is also a necessary lubricant for the compressor and other moving parts in the air conditioning unit. Check the coolant annually and, possibly monthly, during hot summer months. Topping off the coolant may require an HVAC technician but maintaining the proper level keeps the air the coldest and prevents mechanical problems inside the machine.
Whether gas or electric, the heating unit has burners or elements for heating the exchanger. The exchanger is a box where cold air enters and warm air exits. The burners do not directly heat the air; they heat the exchanger. Check all the burners for proper temperatures. If the heating unit is gas-fired, ensure all the burner flames are at the proper height. Flames that are too high or too low can affect the heat exchanger’s efficiency. An adjustment screw supplying the gas to the burner alters the flame height. Electric elements (similar to a stove eye) must also reach proper temperatures. Over time, the element may lose heat capacity and will need to be replaced
Source: www.ehow.com; Wesley Tucker.