Does the arrow “up” on the cabin filter frame in the same direction of air flow or not? The replacement filter I just received has an “air flow” arrow, and the instructions say to put it in with the arrow pointing “DOWN”. Which is in the opposite direction of what the arrow in the case shows as “up”. What is the direction of air flow? Down going up? Or up going down?
Some makes of filter come marked with an arrow for airflow direction, and others come marked with an arrow for UP. While I don't know for sure the airflow direction in a Prime, it is definitely down for Gen 1 through Gen 3 and the geometry of the dash and heater box pretty strongly weigh in that direction. So if you have a filter with an airflow arrow, point it down. If you have a filter with an up arrow, point it ... up.
I'm sure the Prime has the same air box design as Gen 4 Hybrid, so air flows from top to bottom through the filter.
Yes I have a 2022 Prime LE and I just got a Fram CF 12157 cabin filter that has air flow arrows. The housing on the car says UP on it but the filter should be installed with the arrows pointing down indicating air flow that goes in the top of the filter down to the air system. A bit counter-intuitive but VERY important for the system.
