# Air handling, economizers, filtration

Part ID: 6.04 · Layer 6 (Facility cooling & HVAC)

Air-handling units, outside-air economizers, and filtration equipment that condition and clean the air supplied to air-cooled data center halls.

Works alongside CRAH and CRAC units (6.03) to bring in and treat air — economizers use outside air directly when ambient conditions allow, cutting mechanical cooling hours, while filtration protects electronics from particulates and, in some locations, gaseous contamination. Economizer-heavy designs are the air-side equivalent of the "free cooling" strategy in the chilled-water loop that dry coolers enable (6.02): both trade on the same logic that more hours without compressors lowers energy draw and the load chillers carry. As AI halls push chip heat into liquid loops instead, the marginal role of air handling narrows toward conditioning the building shell and the residual air-cooled equipment rather than carrying the full IT heat load, though cleanliness filtration standards generally hold regardless of cooling method. Investors should watch how economizer hours and air-handling scope get resized in liquid-first designs versus legacy air-cooled fleets.

**AI delta:** As liquid cooling takes over the chip heat load, air handling and economizer capacity is increasingly sized to the building envelope and residual equipment rather than to full IT load, shrinking its role relative to the facility water loop.

## Companies

| Company | Role | Confidence | Ownership | Ticker | Note |
|---|---|---|---|---|---|
| Daikin | manufacturer | inferred | public | 6367.T |  |
| Donaldson | manufacturer | inferred | public | DCI |  |
| Johnson Controls | manufacturer | inferred | public | JCI |  |
| Munters | manufacturer | inferred | public | MTRS.ST |  |
| Parker Hannifin | manufacturer | inferred | public | PH |  |
| Systemair | manufacturer | inferred | public | SYSR.ST |  |
| Trane | manufacturer | inferred | public | TT |  |
| Camfil | manufacturer | inferred | private |  |  |
| Freudenberg | manufacturer | inferred | private |  |  |
| Mann+Hummel | manufacturer | inferred | private |  |  |

Confidence tags: disclosed = company/filing statement; reported = trade press or partner list; inferred = taxonomy lead.