What the Air Box Jr HEPA Refill Restores
A loaded HEPA element does not stop filtering, it starts choking. This is the replacement cartridge for the Junior intake housing, measuring 3 x 12 x 12 in and rated MERV 13. It holds 98% of insects, moulds, spores, pollen, dust and dander down to 0.3 microns. The symptom of a spent element is falling airflow rather than falling filtration, since a clogged filter traps more and passes less. The housing is rated to 250 CFM maximum and 125 recommended, and that recommended figure drifts downward as the cartridge loads. Replacing on airflow rather than on a date is the honest approach.
Keeping a MERV 13 Replacement Cartridge in Stock
A merv 13 replacement cartridge is worth having on the shelf before it is needed. An intake filter that clogs mid-crop leaves a choice between running unfiltered and running starved of air. Neither is a good option in flower. Change the pre-filter first and more often, since it catches the coarse load and protects the pleats behind it. It is the least costly item in the stack, and it decides how long this cartridge lasts. Handle the element by its frame and avoid pressing on the media, as a crushed pleat is a bypass path. Seat it flat against the gasket and check the perimeter before closing the housing. A filter that looks grey rather than white has been working, and one that looks black has been working for too long.
Key Features
- MERV 13 HEPA media: Restores filtration to 98% of particles down to 0.3 microns.
- 3 x 12 x 12 in cartridge: The exact element for the Air Box Junior intake housing.
- Replace on airflow: A loaded HEPA chokes before it stops filtering, so airflow is the real signal.
- Protect it with the pre-filter: The coarse load belongs on a low cost part changed more often.
- Housing stays in place: Only the media is consumed, so the unit and ducting are untouched.
Technical Specifications
| Specification | Value |
|---|---|
| Brand | Air Box |
| Product | Junior HEPA Refill Cartridge |
| Part Number | 4501-H |
| Fits | Air Box Junior HEPA intake housing |
| Filter Type | MERV 13 HEPA |
| Cartridge Size | 3 x 12 x 12 in |
| Filtration | 98% of airborne particles down to 0.3 microns |
| Housing Rating | 250 CFM maximum, 125 CFM recommended |
| Change With | Junior pre-filter refill |
| 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 |