How Many of This Air Box Refill Cartridge Your Unit Takes
The number in the model name is the cartridge count, and that is the part people get wrong. An Air Box 1 holds one cartridge, an Air Box 2 holds two, and an Air Box 3 holds three. This listing is a single cartridge, measuring 12 x 20 x 1 in of 100% activated charcoal drawn from premium virgin coconut shell. Refilling rather than replacing is the whole argument for a box-style filter, since the steel housing outlives a dozen cartridges. Service life runs roughly 18 to 24 months, though temperature and humidity move that either way. A cartridge that smells like the room rather than like carbon is finished, whatever the calendar says.
Swapping an Airbox Replacement Filter Without Dropping the Housing
An airbox replacement filter slides out of the front of the housing, which means the ducting stays connected and the unit stays hung. That is the practical advantage over a cylindrical filter, where replacement means taking the whole thing down and re-taping two collars. Change cartridges as a set rather than one at a time on a multi-cartridge box. A fresh cartridge next to a spent one just channels air down the path of least resistance. Handle them by the frame. Compacted carbon sheds dust when it is squeezed, and that dust ends up in the fan. Log the date on the frame with a marker; guessing at the next change is how rooms start smelling.
Key Features
- One cartridge per unit number: Air Box 1 takes one, Air Box 2 takes two, Air Box 3 takes three of these.
- 12 x 20 x 1 in cartridge: The common size across the three smallest Air Box housings.
- Premium virgin coconut charcoal: 100% activated carbon rather than a reactivated or blended media.
- Front loading swap: Slides out without unhanging the unit or breaking the duct connections.
- 18 to 24 month service life: A stated working window, varying with temperature and humidity in the room.
Technical Specifications
| Specification | Value |
|---|---|
| Brand | Air Box |
| Product | Refill Carbon Cartridge |
| Part Number | HT4502 |
| Fits | Air Box 1, Air Box 2, Air Box 3 |
| Quantity | Single cartridge |
| Cartridge Size | 12 x 20 x 1 in |
| Media | 100% activated charcoal, premium virgin coconut |
| Cartridges Per Housing | 1 for Air Box 1, 2 for Air Box 2, 3 for Air Box 3 |
| Typical Service Life | 18 to 24 months |
| Max Operating Temperature | 176 F |
| Returns | 14 days from delivery if unused, with a 30% restocking fee and return shipping paid by the customer, per the Air Box manufacturer policy |