Free tool

CR box filter reminder

MERV-13 filters gradually load with the particles they capture and move less air. Enter when you fitted them and how dusty your home is for an estimated replacement date.

Our recommendation
CleanAirKits Luggable XL Ultra (7-Fan)

681 m³/h CADR, MERV-13, under 35 dB — powerful whole-home clean air — no proprietary lock-in, ships from the UK.

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Install date:   Environment:

Signs a filter is due (whatever the date)

Detail: when to replace CR box filters and the replacement schedule.

Related guides

guide
When to replace

The full guidance.

guide
Replacement schedule

Plan ahead.

guide
Troubleshooting

Restore lost airflow.

Frequently asked questions

How often should I replace CR box filters?

Typically every 6–12 months in an average home, sooner with pets, heavy dust, smoke or pollen. The reminder tool estimates a date from your environment.

How do I know filters are due early?

Weaker airflow at the same speed, a grey loaded filter surface, and slower air-quality recovery are the signs — replace regardless of the calendar.

Can I vacuum filters to extend life?

Gently vacuuming the intake surface clears coarse dust and extends life, but MERV-13 media is meant to be replaced, not washed.