Maybe it’s a case of out of sight out of mind, or that most motorists probably don’t even know that their car has one, but it is easy to overlook replacing the Cabin Air Filter at a service. Typically, these have a life of 15,000km or one year.
NAPA advise that failing to service them can have a number of negative outcomes including;
• Poor airflow resulting in lacklustre defogging/defrosting.
• Unpleasant odours.
• Premature failure of the blower motor in extreme cases.

Apart from avoiding the downsides they are also a great add-on sale at a service!
Possibly even more important in today’s world, the better brands have either antibacterial properties or even medical grade filtering.
NAPA offers their house brand NAPA Cabin air filters, these are activated carbon filters with an additional anti-viral coating to protect occupants from pollen, nasty odours, harmful gases, mould, fungus and certain viruses such as Influenza Type A.
In addition, they offer the Ryco N99 microshield range of cabin air filters which includes anti-viral and anti-bacterial layers. The N99 is more efficient at catching particles under 1 micron (up to 500 percent more than regular filters), they contain 60 percent more media than their predecessors. The antiviral layer works with Influenza A strains.  The N99 designation means that at 0.3-micron size it must be 99 percent efficient, the most common N95 medical grade masks only have to be 95 percent efficient!
Whilst we are looking at servicing the HVAC system another common problem is odours from built up contaminants within the evaporator core, NAPA also offer the Kool-It evaporator and heater core cleaner. This comes in an aerosol can with tubing and produces foam which is introduced via the evaporator drain hose, leave for 15 mins and then run the system at idle and the foam condenses and drains out of the system taking mould and odours with it. NAPA and Ryco filters available from NAPA Auto Parts 0800 800 073