PAH Central-Station Air Handling Unit
Modular central-station air handling unit spanning 600 to 94,000 L/s, built to Eurovent standards with thermally broken double-wall construction and configurable heat-recovery, filtration, and humidification sections.
The PAH is Petra Engineering's central-station air handling unit, designed for projects where a packaged rooftop or split system cannot match the required airflow, filtration grade, or process flexibility. Standard factory-assembled units cover 600–21,000 L/s (1,270–44,500 CFM) as single pieces; custom-engineered multi-section assemblies reach 94,000 L/s (200,000 CFM), placing the PAH within scope for the largest airport terminal, hospital, or convention-centre supply-air systems.
The double-wall casing uses G-90 galvanized steel with 50 mm foam-injected insulation at a minimum 3 pcf density, and thermally broken panel perimeters to prevent condensation bridges — important in humid Gulf climates where the delta between supply-air and ambient can exceed 25 °C. Flat roof covers with standing seams and integrated rain gutters protect internal components on exposed rooftop plant. All standard doors use machine-applied foam gaskets to eliminate air leakage paths that compromise measured fan performance and filtration efficiency.
Filtration stages span MERV 1–8 as standard with optional bag and HEPA upgrades, making the PAH configurable for airport concourse air quality targets, healthcare infection-control requirements, or industrial-process cleanliness. Coil sections use seamless copper tubes mechanically expanded into aluminium fins, pressure-tested to 3,100 kPa underwater. Heat-recovery options — thermal wheel, heat pipe, or cross-flow plate exchanger — reduce fresh-air conditioning load, directly cutting chiller and boiler plant sizing in high-ventilation-rate occupancies such as terminals with continuous passenger turnover. Variable frequency drives on fan sections and modulating dampers integrate with BMS for demand-controlled ventilation.
Technical specifications.
| Standard airflow range (single piece) | 600–21,000 L/s |
| Custom airflow range | Up to 94,000 L/s |
| Standard airflow (CFM) | 1,270–45,000 CFM |
| Casing insulation | 50 mm foam injection, ≥3 pcf density |
| Casing steel | Double-wall G-90 galvanized, thermally broken |
| Coil pressure test | 3,100 kPa (underwater) |
| Filter grades (standard) | MERV 1–8 (pleated, synthetic, aluminium) |
| Filter grades (optional) | Bag filter, HEPA |
| Fan type | DWDI centrifugal (SWSI optional) |
| Certification | Eurovent performance certified |
Use cases.
- ›Airport terminal supply-air systems requiring large single-unit or multi-section assemblies beyond 45,000 CFM with upgrade-path to HEPA filtration
- ›Hospital, hotel, and high-occupancy commercial buildings where thermally broken double-wall construction prevents condensation at high humidity differentials
- ›Projects with high fresh-air fractions (100% OA/DOAS configurations) where heat-recovery wheels or plate exchangers reduce chiller and boiler plant sizing
- ›Industrial or airport-adjacent facilities where demand-controlled ventilation via VFD fans and BMS-integrated modulating dampers is required for energy code compliance
- ›Retrofit installations in existing plant rooms where modular section-by-section assembly avoids the structural constraints of single large-piece delivery
- ›GCC climate applications where UV-C sections and enhanced drain-pan design address condensate management in continuously high-humidity return air