What happens when you do not change cabin air filter/Passenger compartment air filter.
This filter has many name references.
Change your A/C filter or pollen regularly and breath clean air. Pollen filters get dirty therefore restrict good air circulation.
Signs of bad A/C filter
.Bad smell when you turn on A/C
.Restricted air flow
. Pollen and contaminated air not filtered causing sinus trouble to occupants that have allergy troubles
.Poor window fog clearing