Jeep 2007 Patriot - Manual (Page 229)

NOTE: Continuous use of the recirculate mode may
make the inside air stuffy and window fogging may
occur. Extended use of this mode is not recommended.
In cold or damp weather, the use of the Recirculate
position will cause windows to fog on the inside because
of moisture build up inside the vehicle. For maximum
defogging, select the Outside Air position.
NOTE: Recirculation Mode will not operate in floor, mix
or defrost modes.
Air Filtration System – If Equipped
An air filter is included in the optional Security Group.
Filter media includes a particle filtration layer and a
charcoal layer. The filter will reduce, but not eliminate,
diesel and agricultural smells. The filter acts only on air
coming from outside the vehicle; it does not filter air
inside the passenger compartment. See the maintenance
schedule for the filter change interval. The air filter
change interval coincides with engine oil and filter
change intervals. As with oil changes, the interval is
shorter for heavy duty service or dusty conditions. See
your authorized dealer for service.
228 UNDERSTANDING YOUR INSTRUMENT PANEL