The filter in your Northbridge Ma HVAC system should be changed at least twice a year – once just before the heating season begins and once before the cooling season begins. If you live in a particularly dusty area, you may want to change it more often. Always replace the filter with a new filter that has the same airflow rating. Again, We caution, “Be careful with ‘air purifying’ or HEPA filters,” he says, “because they can dramatically reduce airflow in your system. That can cause the indoor coil to freeze because of the reduced airflow.”
Locate the filter enclosure on the indoor furnace/AC where the large fresh air return duct enters the unit. You may need a screwdriver to turn the latch to open the door to the filter enclosure. Remove the old filter and install the new filter, matching the air-flow direction arrows on the filter to the arrows on the unit. Close and latch the door.