AC Infinity Activated Carbon Filter 100 mm

An inline carbon filter with a 100 mm collar, filled with Australian RC412 charcoal in a 38 mm bed. Rated to 210 CFM (357 m³/h).

This is the smallest size in the range and the default choice behind a 100 mm fan. There is one question everybody asks sooner or later, and the answer is rarely printed on a box.

How you know a filter is finished

Activated carbon works by adsorption: odour molecules attach to the enormous internal surface of the granules. That surface is finite. At some point it is occupied and the smell simply passes through, with nothing visible on the filter to show it.

So there is no gauge and no colour indicator. The signal is your nose: if you can smell something at the outlet that was not there a month ago, the carbon is saturated. That is also a good reason to put the outlet somewhere you walk past now and then.

What sets the service life is not time but the number of cubic metres that have passed through, and how humid that air was. A filter running at half speed all cycle lasts considerably longer than the same filter behind a fan sitting at full power day and night.

Do not confuse the carbon with the pre-filter. The white sleeve around the body catches dust and fluff and goes in the washing machine. A clean pre-filter keeps air reaching the carbon, but it does not make saturated carbon active again. Wash the sleeve regularly, and replace the filter when the smell returns.

Build and fitting

The flanges are aluminium and the body is galvanised steel mesh with a coating against rust, which matters in a humid room. The filter can sit on either the suction or the pressure side of your fan; the suction side is more usual, because the odour is then removed before the air enters the ducting.

A washable pre-filter cloth is included. Your fan's duct clamp fits straight onto the flange.

Technical Specifications:

• Model: AC-DCF4
• Collar: 100 mm (4 inch)
• Maximum airflow: 210 CFM (357 m³/h)
• Carbon: Australian RC412, 1200+ IAV
• Carbon bed thickness: 38 mm
• Length: 330 mm
• Material: aluminium flanges, coated steel mesh
• Works best: below 55% relative humidity
• Included: washable pre-filter cloth

Frequently asked questions

How long does a filter like this last?
It depends on how much air passes through and how humid it is, not on the calendar. Your nose at the outlet is the most reliable indicator.

Can I replace the carbon myself?
Not on this model, the body is sealed. If you would rather refill than replace, look at the refillable carbon filter kit in 100 mm.

Does the filter go before or after the fan?
Usually before, on the suction side. The odour is then gone before the air enters your ducting.