XFDD3-650-01J Campus Fresh Air Ventilator
The Legom XFDD2-650-01J Campus Fresh Air Ventilator is a high-capacity ceiling-mounted fresh air unit designed for classrooms, offices, and commercial spaces requiring continuous large-volume ventilation with multi-stage air purification. With a rated air volume and CADR of 650m³/h, the XFDD2-650-01J delivers fresh outdoor air at a scale suited to spaces with high occupancy density where CO2 concentration, PM2.5, formaldehyde, allergens, and airborne pathogens accumulate rapidly.
The unit combines four critical components in a single ceiling-mounted housing: an intelligent controller, a negative ion module for sterilization and fine particle neutralization, a HEPA filter for physical PM2.5 and allergen capture, and an AC centrifugal fan capable of overcoming duct resistance at static pressures up to approximately 120Pa. At 496 × 496 × 298mm and ceiling-mounted installation, the unit occupies no floor space in the served room and operates at ≤55dB(A).
Key Benefits
- High-capacity 650m³/h air volume – Rated air volume and CADR both at 650m³/h, making this unit capable of providing multiple full air changes per hour in classrooms and offices of 100m² or larger at standard ceiling heights
- CO2 concentration reduction – Continuous fresh air supply at high volume dilutes CO2 buildup from occupant respiration, maintaining cognitive performance and alertness in classrooms and meeting rooms where CO2 accumulation is a documented cause of reduced concentration
- HEPA filter for physical PM2.5 and allergen capture – Unlike ion-only systems, the HEPA filter physically captures fine particles including PM2.5, pollen, mold spores, and dust, providing a mechanical filtration stage that does not depend on electrical ionization alone
- Negative ion module for sterilization – The combined negative ion system neutralizes airborne viruses, bacteria, and fine particles in the air stream complementing the HEPA filter’s physical capture function
- Formaldehyde and allergen elimination – Targets gaseous decoration pollutants including formaldehyde alongside particulate allergens and dust, addressing both new-building off-gassing and ongoing allergen loads
- AC centrifugal fan with 120Pa static pressure – Fan capable of overcoming duct resistance in ceiling-mounted installations with moderate duct runs, enabling flexible positioning of the unit relative to the outdoor air intake and exhaust points
- Intelligent control – Integrated controller enables automated operation based on air quality sensing or scheduled programming, reducing manual intervention in managed building environments
- Ceiling-mounted installation – No floor space consumed in the served room; the unit is suspended from the ceiling structure with wall drilling required for duct penetrations
- OEM and ODM customization available – Contact Legom for customized specifications or branding requirements
Technical Specifications
| Parameter | Specification |
|---|---|
| Item No. | XFDD2-650-01J |
| Rated Voltage | 220V / 50Hz |
| Power | 320W |
| Type | Ceiling type |
| Rated Air Volume | 650 m³/h |
| CADR | 650 m³/h |
| Static Pressure | ~120 Pa |
| Noise | ≤ 55 dB(A) |
| Duct Diameter | DN150 |
| Dimensions | 496 × 496 × 298 mm |
| Weight | 20 kg |
| Critical Components | Controller, negative ion module, HEPA filter, AC centrifugal fan |
| Installation Method | Ceiling-mounted (wall drilling required for duct) |
Product Comparison: XFDD2-650-01J vs XFQT-60-01S
| Parameter | XFDD2-650-01J | XFQT-60-01S |
|---|---|---|
| Target application | Campus, classroom, commercial | Residential room |
| Air volume (CADR) | 650 m³/h | 57 m³/h |
| Power | 320W | 12W |
| Filtration | HEPA + negative ion | Ion catalytic only |
| Installation | Ceiling-mounted | Through-the-wall |
| Noise | ≤ 55 dB(A) | 38 dB(A) |
Application & Use Cases
- School classrooms and lecture halls – The primary named application. High occupancy density combined with children’s and students’ sensitivity to CO2 and indoor air pollutants makes large-volume continuous fresh air supply with multi-stage purification a priority in educational buildings
- Office spaces and meeting rooms – High CO2 concentrations in enclosed meeting rooms are a documented cause of reduced decision-making quality and productivity. The XFDD2-650-01J provides sufficient air volume to maintain CO2 levels below cognitive impact thresholds in spaces up to approximately 200m²
- Newly built or recently renovated commercial spaces – Where formaldehyde and VOC off-gassing from building materials and furnishings requires active dilution and capture during the initial occupancy period
- Medical waiting rooms and clinics – The HEPA filter and negative ion module together provide a meaningful reduction in airborne pathogen load in high-risk shared indoor environments
- Retail and hospitality spaces with high foot traffic – Large air volumes and intelligent control enable automatic response to occupancy-driven changes in air quality in retail, restaurant, and lobby environments
- Public buildings requiring documented air quality management – Intelligent control with air quality sensing supports compliance with indoor air quality standards in government, institutional, and educational buildings
Installation Notes
- Installation is ceiling-mounted. The unit must be suspended from the ceiling structure using appropriate hangers or brackets capable of supporting the 20kg unit weight plus dynamic load from fan vibration
- Wall drilling is required for the DN150 duct penetrations connecting the unit to outdoor fresh air intake and exhaust points. Plan duct routing before finalizing the installation location
- The unit requires a 220V / 50Hz power supply routed to the ceiling installation point. An independent circuit breaker is recommended for safe isolation during maintenance
- Allow adequate service clearance below and around the unit for filter access and periodic HEPA filter replacement. Verify ceiling height and structural clearance before installation
- Connect ductwork to the DN150 outlets with appropriate duct connectors and sealant to prevent air leakage that would reduce effective supply volume
- Standard installation requires wall drilling — refer to the user manual for full installation procedures, fixing methods, and charging standards specific to this model
- The HEPA filter requires periodic replacement depending on local air quality conditions and operating hours. Maintain a filter replacement schedule to ensure sustained purification performance
Frequently Asked Questions
What room size is the XFDD2-650-01J suited for?
With a CADR of 650m³/h, the XFDD2-650-01J can provide approximately 5 to 6 air changes per hour in a room of 100m² with a 3-metre ceiling (300m³ volume), or approximately 2 to 3 air changes per hour in a 200m² room. For classrooms typically designed for 30 to 50 students, this volume is sufficient to maintain CO2 well below the 1000ppm threshold associated with cognitive impairment under normal occupancy conditions. For very large spaces or auditoriums, multiple units or a higher-capacity system may be required.
How does this unit differ from the XFQT-60-01S residential model?
The XFDD2-650-01J is a commercial and institutional-grade unit designed for high-occupancy spaces with correspondingly high ventilation requirements. Its CADR of 650m³/h is more than 11 times greater than the XFQT-60-01S at 57m³/h. It also adds a physical HEPA filter stage not present in the XFQT-60-01S, uses a ceiling-mounted installation rather than through-the-wall, and draws 320W versus 12W. Choose the XFDD2-650-01J for classrooms, offices, and commercial spaces; choose the XFQT-60-01S for individual residential rooms.
Does the HEPA filter need to be replaced regularly?
Yes. The HEPA filter is a physical filtration medium that captures particles by trapping them in the filter material. Over time the filter becomes loaded with captured particles, reducing airflow and filtration efficiency. The replacement interval depends on local outdoor air quality, operating hours, and the level of indoor pollution sources. In high-pollution urban environments or spaces with heavy occupancy, more frequent replacement is required. Refer to the user manual for the manufacturer’s recommended replacement schedule and filter specification.
What is intelligent control and how does it work?
The integrated controller enables the unit to operate automatically based on air quality conditions or pre-programmed schedules rather than requiring manual on/off control. In air quality-responsive mode, the unit adjusts fan speed or activates based on CO2 concentration, PM2.5 levels, or other sensed parameters. In scheduled mode, the unit operates during defined occupied hours and reduces or stops operation outside those hours. Contact the Legom team for details on the controller’s specific sensing inputs and automation capabilities for this model.
Can multiple units be installed in a single large space?
Yes. For spaces requiring more than 650m³/h of fresh air supply — such as large open-plan offices, cafeterias, or gymnasium halls — multiple XFDD2-650-01J units can be installed to achieve the required total air volume. Unit placement should be planned to ensure even distribution of fresh air supply and exhaust across the space. Contact the Legom team for multi-unit layout guidance for your specific project.
OEM & ODM Customization
Legom supports OEM and ODM services for the XFDD2 Campus Fresh Air Ventilator series. Our engineering team can customize specifications, branding, and system integration configurations to match your project requirements. All customization projects are handled with strict confidentiality. Contact us via WhatsApp or info@legomsmart.com.
User Manual
Product information last reviewed by the Legom Technical Team. For the most current specifications, refer to the official datasheet or contact our sales team.
Custom OEM & ODM Solutions
Legom is a direct manufacturer offering end-to-end OEM and ODM services. With our in-house engineering and production capabilities, we work closely with distributors and system integrators to deliver fully customized solutions under strict NDA.
