PYHL-14A / HL3-2A Mixed-flow Fan

The PYHL-14A / HL3-2A mixed-flow fan is a state-of-the-art ventilation device that represents a significant advancement in air movement technology. Unlike conventional axial fans that excel at high airflow but struggle with pressure, or centrifugal fans that deliver high pressure but consume substantial space and energy, the mixed-flow design achieves an optimal balance. The air flows through the fan in both axial and radial directions relative to the shaft, enabling the unit to develop higher pressures than axial fans while maintaining a compact, in-line footprint.

GRAD Group has engineered this fan series with a wheel diameter range spanning from 272 mm to 1,564 mm, covering 24 distinct sizes from 2.5A through 14A. The comprehensive performance envelope accommodates airflow volumes from as low as 450 m³/h up to an impressive 135,000 m³/h, with total pressure capabilities ranging from 50 Pa to 1,900 Pa. This wide operational range ensures that system designers and facility managers can select the precisely correct configuration for their specific ventilation requirements without over-specifying or compromising performance.

The impeller design incorporates meridian-accelerating conical hub geometry combined with spatially twisted blades welded to the hub. This sophisticated aerodynamic configuration is the result of computational fluid dynamics optimization, ensuring that air passes through the fan with minimal turbulence and maximum energy transfer. The cylindrical casing houses strategically positioned downstream guide vanes that straighten the airflow, reducing swirl losses and further enhancing overall system efficiency. GRAD Group subjects every impeller to dynamic and static balancing tests with balance precision achieving Grade 5.6 or better, guaranteeing vibration-free operation throughout the fan's service life.

For applications demanding acoustic discretion, GRAD Group offers silencer-equipped versions. The inlet silencer features a streamlined arc design with micro-perforated panels and sound-absorbing materials such as ultra-fine glass wool or PF acoustic boards, effectively reducing noise levels by 3 to 6 decibels. For the most noise-sensitive environments, cabinet-enclosed versions (HLF series) provide additional sound attenuation of 5 to 10 decibels through composite silencer box construction. These options make the PYHL-14A / HL3-2A series suitable for installations where acoustic comfort is paramount, such as hospitals, libraries, and office environments.

The PYHL-14A variant deserves special attention for its fire safety capabilities. Building upon the HL3-2A foundation, GRAD Group has equipped this model with a high-temperature motor rigorously tested according to GA211-2009 (the national standard for fire smoke exhaust fan high-temperature testing). The fan has successfully passed the 3C compulsory certification administered by the Fire Product Qualification Assessment Center. This certification confirms that the PYHL-14A can operate continuously for more than 60 minutes in media temperatures reaching 280°C, and withstand 20 hours of operation at 100°C without damage. This dual-purpose capability—serving both routine ventilation and emergency smoke exhaust—makes the PYHL-14A an indispensable component of modern building fire protection systems.

1. Hybrid Aerodynamic Design for Superior Performance

The PYHL-14A / HL3-2A fan uniquely combines the high-volume airflow characteristics of axial fans with the elevated static pressure capabilities of centrifugal fans. This hybrid approach delivers a pressure rise in a single stage that would typically require multi-stage axial fan configurations, while maintaining the compact in-line form factor that simplifies ductwork integration. The result is a ventilation solution that occupies less space, weighs less, and costs less to install than comparable centrifugal systems.

2. Exceptional Energy Efficiency

Mixed-flow impeller technology enables these fans to achieve peak efficiencies approaching 80%, significantly outperforming comparably sized tubular centrifugal and vane axial alternatives. The optimized blade geometry reduces the required motor horsepower while maintaining or exceeding the airflow and pressure delivery of less efficient fan types. For clean air applications at moderate static pressures, the mixed-flow fan is typically the most efficient and quietest selection available. When paired with variable frequency drives, the fan's energy consumption decreases according to the cube fan law, delivering substantial operational cost savings over the equipment's lifetime.

3. Fire-Rated Smoke Exhaust Capability (PYHL-14A)

The PYHL-14A model incorporates a specially engineered high-temperature motor that enables continuous operation at 280°C for 60 minutes or longer. This fire-rated performance, validated through GA211-2009 testing and 3C certification, ensures that the fan remains operational during building fires to exhaust toxic smoke and heat. This capability is critical for maintaining tenable conditions for building evacuation and providing firefighters with improved visibility and reduced thermal exposure when entering the blaze.

4. Versatile Speed Control Options

GRAD Group offers multiple speed control configurations to match diverse application requirements. Single-speed models provide fixed-capacity operation for straightforward ventilation needs. Dual-speed versions enable two-stage调速, categorized as S1, S2, and S3 with different speed ratios. For applications requiring continuous capacity modulation, variable-frequency drive (VFD) equipped models with变频 motors provide infinite speed control, with the recommended frequency adjustment range locked between 25 Hz and 50 Hz for optimal motor protection and performance.

5. Robust Construction and Durability

Manufactured from high-quality steel with corrosion-resistant treatment, these fans are built for demanding industrial environments. The impeller blades are formed through hydraulic stamping from steel plate, while the hub undergoes hydraulic tensile forming. The outer cylinder flange features integral roll-formed edges that eliminate weak points and improve structural integrity. All components are designed to withstand the rigors of continuous operation in environments with dust concentrations up to 150 mg/m³ and non-corrosive, non-spontaneous combustion gases.

6. Low Noise Operation

The combination of precision-balanced impellers, optimized aerodynamic design, and optional silencer configurations ensures exceptionally quiet operation. For applications where noise is a critical concern—such as hospitals, educational facilities, concert halls, and libraries—the PYHL-14A / HL3-2A series delivers acoustic performance that rivals or exceeds dedicated low-noise fan products. The inlet silencer design follows streamlined aerodynamic principles that minimize pressure drop while maximizing sound attenuation.

7. Customization and Special Configurations

GRAD Group recognizes that no two ventilation projects are identical. Customized airflow, pressure, voltage, and dimensional configurations are available to meet specific project requirements. For hazardous environments, explosion-proof versions with EXdIIBT4 classification can be supplied. For corrosive atmospheres, corrosion-resistant material upgrades are available. This flexibility ensures that system designers can specify the exact fan configuration needed without compromising performance or safety.

Commercial Buildings

The PYHL-14A / HL3-2A series is extensively deployed in commercial structures including office towers, shopping centers, hotels, and mixed-use complexes. In these settings, the fans serve multiple functions: supplying fresh outdoor air to occupied spaces, exhausting stale or contaminated indoor air, and providing pressurization for stairwells and elevator shafts. The low noise characteristics make these fans particularly suitable for installations adjacent to occupied spaces, while the compact in-line design simplifies integration into crowded mechanical rooms and ceiling plenums.

Industrial Facilities

Factories, warehouses, manufacturing plants, and logistics centers benefit from the robust construction and high-capacity performance of these mixed-flow fans. Industrial environments often require ventilation systems capable of handling large air volumes while overcoming the static pressure losses imposed by extensive ductwork networks, dust collection systems, and process exhaust requirements. The PYHL-14A / HL3-2A series delivers the necessary pressure capability while maintaining energy efficiency—a critical consideration for facilities where ventilation systems operate continuously.

Underground Facilities

Parking garages, equipment rooms, tunnels, and civil defense shelters represent some of the most demanding ventilation applications. These enclosed spaces require reliable extraction of vehicle exhaust, heat, and potentially hazardous gases. The PYHL-14A model's fire-rated smoke exhaust capability is particularly valuable in underground parking structures, where vehicle fires can produce toxic smoke that rapidly fills the confined space. The fan's ability to operate at elevated temperatures ensures that smoke extraction continues when it is needed most.

Public Buildings

Hospitals, schools, airports, stadiums, and exhibition centers demand ventilation systems that prioritize indoor air quality, occupant comfort, and acoustic performance. The PYHL-14A / HL3-2A series meets these requirements through efficient air movement that maintains proper air exchange rates, removes airborne contaminants, and operates quietly enough to avoid disrupting sensitive activities. In healthcare facilities, proper ventilation is directly linked to infection control and patient outcomes. In educational settings, adequate fresh air supply has been shown to improve cognitive performance and student attentiveness.

Specialized Applications

Beyond the standard applications, these fans find use in specialized environments including data centers (where cooling reliability is paramount), textile manufacturing facilities, marine and shipboard ventilation systems, and air conditioning projects in civil buildings. The availability of explosion-proof and corrosion-resistant configurations extends the product's applicability to chemical processing plants, fuel storage facilities, and other hazardous locations.

Supply Air

The PYHL-14A / HL3-2A mixed-flow fan functions as a supply air unit, drawing fresh outdoor air through intake louvers and delivering it through ductwork to occupied spaces. The fan's ability to generate moderate-to-high static pressure ensures that air reaches all terminal devices—diffusers, grilles, and registers—with adequate velocity and volume, even in extensive ducted systems with numerous branches and fittings.

Exhaust Air

In exhaust mode, the fan removes stale air, contaminants, odors, and excess heat from interior spaces. This function is critical for maintaining acceptable indoor air quality in accordance with ASHRAE ventilation standards and local building codes. The fan's high-volume capability enables rapid air changes in spaces with high occupancy or significant pollutant generation rates, such as commercial kitchens, industrial workshops, and parking garages.

Smoke Exhaust (PYHL-14A)

The PYHL-14A model's most critical function is emergency smoke exhaust during fire events. When building fire detection systems activate, the fan operates at its fire-rated temperature capacity to extract smoke and superheated gases from the fire zone. This function serves multiple life-safety purposes: maintaining visibility for evacuation routes, reducing toxic gas concentrations, limiting smoke migration to unaffected building areas, and improving conditions for firefighter access and fire suppression operations. The 3C certification provides building owners, facility managers, and authorities having jurisdiction with documented assurance of the fan's fire performance.

Air Circulation and Recirculation

In recirculation applications, the fan moves air through air handling units, heat recovery systems, and dedicated recirculation loops. This function supports temperature equalization, humidity control, and contaminant dilution without introducing outdoor air. The fan's efficiency at moderate static pressures makes it particularly well-suited for recirculation applications where duct losses are significant but not extreme.

Variable Air Volume System Integration

When equipped with variable frequency drives, these fans seamlessly integrate into variable air volume (VAV) systems. The VFD enables the fan to modulate airflow in response to changing building thermal loads and occupancy patterns, delivering only the ventilation capacity actually required at any given moment. This modulation capability translates directly into energy savings, as fan power consumption decreases with the cube of the airflow reduction.

Pressurization

The fan can function as a pressurization unit for stairwells, elevator shafts, and smoke control zones. In fire scenarios, stairwell pressurization prevents smoke infiltration into escape routes, maintaining tenable conditions for building occupants during evacuation. The fan's pressure capability ensures that the required pressure differentials are maintained even with doors opening and closing during evacuation.

Q: What is the difference between a mixed-flow fan and an axial fan?

A: A mixed-flow fan combines the high airflow of an axial fan with the higher pressure performance of a centrifugal fan.

Q: Can different specifications be customized?

A: Yes. OEM and ODM services are available for customized models and technical parameters.

Q: What material is used?

A: The standard configuration includes a carbon steel housing and a high-strength steel impeller.

Q: Where is this fan commonly used?

A: It is widely used in commercial buildings, factories, underground parking garages, and public facilities.

Q: What is the delivery time?

A: Standard products are generally delivered within 15–25 days, depending on the order quantity.

Q: Do you provide technical support?

A: Yes. We provide product selection, installation guidance, and after-sales technical support.

Looking for a reliable mixed-flow ventilation solution? Contact Jinan Hongpeng Ventilation Equipment Co., Ltd. today for professional consultation and competitive quotations.