400m³/h Compact Air Purifier

The Defaee 400m³/h Compact Air Purifier is a high-performance air cleaning device engineered for small to medium-sized spaces. Delivering a rated airflow of 400 m³/h, it provides consistent air circulation and purification for areas of 30–60 ㎡ (based on a ceiling height of 2.6–3.0 m). Typical applications include hospital consultation rooms, diagnostic spaces, small laboratories, private offices, residential bedrooms, and private dining rooms.

Developed by DeFa Environmental Equipment (Ningbo) Co., Ltd. — a technology-driven manufacturer with over 20 years of expertise in environmental remediation and air pollution control — this unit integrates a modular multi-stage filtration architecture with an intelligent monitoring system. The design balances dependable purification performance, quiet operation, and straightforward maintenance. It effectively removes airborne particulates, microorganisms, and a range of gaseous pollutants, addressing the strict air cleanliness and stability requirements of both professional and residential environments.

Core Technical Specifications

Purification System & Operating Principle

The unit employs a three-stage filtration architecture: Pre-filter + Composite High-efficiency Filter + Optional Supplementary Modules. This progressive design targets different pollutant categories:

• Pre-filter: Fabricated from polyester fiber media, this washable layer captures larger particles such as hair, dust, and lint. By preventing rapid loading of downstream filters, it extends the service life of the core HEPA composite element and reduces recurring operating costs.
• Composite High-efficiency Filter: The core filtration stage combines an H13-grade HEPA filter (conforming to EN 1822) with an activated carbon composite layer. The HEPA medium intercepts fine particles down to 0.3 μm — including PM2.5, pollen, mold spores, and bacteria — with a single-pass efficiency of ≥99.97%. The integrated activated carbon layer reduces gaseous pollutants such as formaldehyde, TVOC, and odors through physical adsorption, making it suitable for post-renovation environments, cooking fumes, and pet-related odors.
• Optional Additional Modules: Depending on the configuration, the unit can be equipped with a UVC germicidal irradiation module or a negative ion generator. The UVC module targets microorganisms collected on the filter surface, helping to inactivate bacteria and viruses and reduce the risk of secondary contamination. The negative ion module releases negative oxygen ions to promote agglomeration of fine airborne particles and enhance perceived air freshness.

A built-in efficient fan drives air circulation: room air is drawn in through side inlets, passes sequentially through the three filtration stages, and clean air is discharged from the top outlet. With a 400 m³/h airflow, the unit achieves approximately 6–8 air changes per hour in a typical 30 ㎡ space, enabling rapid reduction of indoor pollutant concentrations.

Key Performance Attributes

1. Multi-Contaminant Filtration for Varied Environments

The filtration system is designed to address multiple pollutant types across different settings:

• Healthcare: Reduces airborne bacteria and viral aerosols, supporting infection control protocols.
• Residential: Removes formaldehyde, PM2.5, pet dander, and common household odors.
• Office: Captures particulate matter from printers, copiers, and general occupancy.

2. Quiet Operation and Low Energy Consumption

A DC brushless motor combined with an optimized air duct design limits sound output to ≤55 dB(A) on high speed and ≤35 dB(A) on low speed, enabling overnight use without disturbance. With a rated power of 120 W, continuous 24-hour operation consumes less than 3 kWh of electricity, supporting applications that demand round-the-clock purification, such as hospital spaces and laboratories.

3. Intelligent Monitoring and Simplified Maintenance

The LCD display provides real-time readings of indoor PM2.5 concentration, temperature, humidity, and remaining filter life. Users can select from three fan speeds and set a 1–12 hour timer. The filter replacement reminder indicates the appropriate service interval, helping to maintain consistent filtration efficiency. The side-access filter compartment allows tool-free filter replacement, typically completed in 1–2 minutes by a single person. The control logic draws on DeFa's two decades of field experience in air management systems.

4. Flexible Placement for Multi-Room Use

Four silent universal casters enable the unit to be easily relocated between consultation rooms, offices, bedrooms, and meeting spaces, allowing one device to serve multiple areas as needed. Its compact vertical footprint occupies less than 0.2 ㎡ of floor space.

5. Reliable Construction for Professional Settings

The housing is constructed from ABS flame-retardant plastic or powder-coated cold-rolled steel, providing resistance to corrosion and surface wear suitable for healthcare and laboratory environments. The electrical system incorporates overcurrent and over-temperature protection. Selected models carry medical-grade disinfection certifications to satisfy the regulatory requirements of healthcare facilities.

Typical Application Scenarios

• Healthcare: Hospital consultation rooms, infusion areas, nurse stations, and small laboratories
• Office: Private offices, meeting rooms, and open-plan workstations
• Residential: Bedrooms, living rooms, children's rooms, and home studies
• Commercial: Private dining rooms, small retail spaces, fitness studios, and beauty salons
• Institutional/Laboratory: Small-scale labs and specimen storage rooms

Operation & Maintenance Guidelines

Installation & Placement

No professional installation is necessary. Place the unit on a level surface and maintain a minimum clearance of 20 cm from walls and obstacles to ensure unrestricted airflow at both inlet and outlet. Avoid positioning the device in areas of excessive humidity, high temperature, or direct sunlight to prevent internal damage and filter media degradation.

Daily Operation

Connect to a standard power outlet and press the power button. The device defaults to auto mode, adjusting fan speed based on real-time air quality readings. Manual speed selection (low/medium/high) and a 1–12 hour timer can be set via the touch panel. Optional modules (UVC, negative ions) are toggled on/off using dedicated controls.

Filter Maintenance & Replacement

• Pre-filter: Remove and rinse with clean water every 1–2 weeks; allow to air dry completely before reinserting. Do not wring or scrub aggressively to avoid deformation.
• HEPA Composite Filter: Replace every 6–12 months, depending on operating conditions and pollution load. Replace immediately when the filter replacement indicator activates or when a noticeable decline in airflow or odor removal is observed.
• Replacement Procedure: Power off the unit, open the side filter compartment, remove the used filter, clean any accumulated dust inside the compartment, and install the new filter securely to prevent air bypass.

Cleaning & Storage

Wipe the exterior regularly with a dry cloth; avoid alcohol-based or corrosive cleaning agents. Use a soft brush to gently remove dust from the inlet and outlet grilles. For extended storage, power off, remove the filters, and store the device in a dry, ventilated area away from direct sunlight.

Applications & Value

The 400 m³/h compact air purifier is sized to meet the air cleaning demands of small to medium-sized professional and residential spaces. Compared to larger commercial units, it offers a more maneuverable, installation-free solution with lower total cost of ownership. Relative to basic consumer-grade purifiers, it delivers higher single-pass efficiency and airflow, making it suitable for environments with more stringent air quality requirements. DeFa's product support network and application experience — spanning healthcare, commercial, and residential projects across multiple continents — provide additional assurance of long-term reliability and performance consistency.

Frequently Asked Questions

What room size is this purifier suitable for?

The rated airflow of 400 m³/h is designed for spaces of 30–60 ㎡, assuming a standard ceiling height of 2.6–3.0 m. For rooms with higher ceilings or greater pollution loads, multiple units may be deployed, or our technical team can assist with a tailored recommendation.

How often do the filters need to be replaced?

The washable pre-filter should be rinsed every 1–2 weeks. The H13 HEPA composite filter typically requires replacement every 6–12 months, depending on operating hours and ambient pollution levels. The on-board filter replacement reminder provides a real-time indication based on actual usage.

Does the unit effectively remove formaldehyde and VOCs?

Yes. The integrated activated carbon composite layer within the main filter adsorbs formaldehyde, TVOC, and other common gaseous pollutants. For environments with elevated chemical concentrations, ensuring adequate air changes per hour is recommended; our team can help verify the expected clean air delivery rate for specific compounds.

Is the UVC module safe for occupied spaces?

The UVC irradiation module is enclosed within the unit and directed at the filter surface, so there is no direct exposure to room occupants. The design has been implemented in numerous healthcare and commercial installations without safety concerns when operated according to instructions.

How loud is the unit during nighttime operation?

On low speed, the sound pressure level is ≤35 dB(A), comparable to a quiet library environment. This makes it suitable for bedrooms and patient areas requiring minimal acoustic disturbance.

Can the purifier be moved easily between rooms?

Yes. The four 360° silent casters allow the unit to be rolled smoothly across hard floors. The compact footprint and vertical orientation facilitate movement through standard doorways.

Manufacturer Expertise

DeFa Environmental Equipment (Ningbo) Co., Ltd. has been engaged in the research, production, and application of environmental remediation and air pollution control technologies for over 20 years. Our core competences in high-voltage power supply systems, plasma generation, and intelligent environmental control are embedded across our product lines. Serving a global customer base — with a significant share of output supplied to North American, European, and Asia-Pacific markets — we apply rigorous engineering practices and certified quality processes to every product. From filter media selection and aerodynamic optimization to long-term durability testing, our development approach is centered on delivering reliable, measurable performance for professional users.