Filter Cleaning Products

Filter cleaning products restore a washable air filter instead of replacing it. This category holds filter cleaners, filter oils in aerosols and squeeze bottles, service kits, a cabin filter care kit and restriction indicators that show when a filter needs attention.

An oiled filter traps dirt in two ways. Its fibres stop particles mechanically, and a thin tacky film of oil catches fine dust that would otherwise slip through. A light coating of dirt is normal and even helps filtration, so restriction, not colour, is the better guide to when cleaning is due.

Cleaning reverses the process. The cleaner dissolves the old oil and loosens the dirt, water carries both away, and fresh oil restores the film. The amount of oil matters: too little lets fine dust through, while too much can be drawn into the intake and coat an air mass sensor, upsetting its reading.

The range covers each step:

• Cleaners: spray and pump bottles such as 355 ml, trigger sprayers and bulk containers. Cleaners for dry synthetic media are listed as well.
• Filter oil: aerosols of 204 ml and 408 ml lay an even coat on pleated media, while squeeze bottles allow precise oiling along each pleat. Bulk oil suits a workshop.
• Service kits: cleaner and oil together, as an aerosol kit or a squeeze-bottle kit listed in red, blue or black. Filter oil is usually dyed, so you can see where it has soaked in.
• Cabin filters: a separate care kit made for washable cabin filters.
• Restriction indicators: push-in and screw-in versions fit in the intake after the filter and show how much restriction it has built up.

Tap out loose dirt, spray cleaner on both sides and leave it for the time the label states. Rinse with low-pressure water from the clean side outwards, so dirt leaves the way it came in. Let the filter dry naturally, as heat and compressed air can damage the media.

Oil each pleat lightly, let it wick through and touch up any pale areas. Dry synthetic media get their own cleaner and no oil. Where an indicator is fitted, let it time the next clean rather than the calendar, and check more often after dusty events.