380V AC Centrifugal Fan for AHUs: 695 Pa High-Pressure

Customer Requirement

The OEM procurement manager and HVAC system integrator needed a standardized backward curved fan – 380VAC, 3-phase – that could push 695 Pa of static pressure and still fit inside a  standard AHU or FCU cabinet.

What made this genuinely hard was the environment. These fans would live in unconditioned plenums and outdoor installations, so the operating window had to stretch from -30°C all the way to +60°C. The form factor was equally unforgiving: impeller diameters around 225–250 mm, total depth under 100 mm—standard cabinet rails don’t leave much room to play with. Reliability expectations sat at 30,000 hours L10 minimum, and for anything headed to Europe, CE marking against EN 60335-1 wasn’t up for debate. That set of constraints became the brief for LW26031110, an internal project aimed at locking down specs for two standard catalog models.

Engineering Solution

Motor choice was the first real decision point. While Longwell is a leader in high-efficiency EC motors, an AC induction motor was deliberately selected for this product series. This decision targeted cost-sensitive OEM applications where the granular speed control of an EC fan was unnecessary. Adding an external controller and a premium EC motor would inflate the BOM for capability the application doesn’t need. A 3-phase AC motor plugs right into the same 380 VAC supply the rest of the equipment uses—no extra boxes, no extra wiring, no extra headaches.

From there, two frame sizes split the performance envelope. The 225 mm model, LWBA2D225-092NT-11, leans into pressure: 695 Pa at 60 Hz, built for systems with dense filter banks or restrictive ducting. The 250 mm sibling, LWBA2D250-092NT-15, favors airflow—1,524 m³/h—for ventilating bigger spaces.

One material choice worth calling out: different impellers for different jobs. The 225 mm unit runs a PA66 plastic impeller. It’s light, stiff, and lets the blade geometry get aggressive enough to manage acoustics. The 250 mm fan switches to SGCC galvanized steel. At that diameter and tip speed, plastic would start dancing—steel keeps the balance honest. Both motors carry Class F insulation with a thermal cutout set between 150–160 °C, which gives a comfortable margin even at the +60°C ceiling.

Technical Specifications

The specifications show two distinct performance points for 380 VAC systems. The LWBA2D225 model is optimized for higher static pressure in constrained spaces, while the LWBA2D250 model prioritizes greater air volume, making it suitable for larger air handling units.

Technical Documentation

The motorized impeller design of the LWBA series for compact plenum integration.

The following documents provide the definitive technical data required for system design, qualification, and procurement. They represent the final, approved deliverables of the engineering process.

• Datasheet: LWBA2D225-092NT-11: This PDF contains the full technical datasheet for the 225mm model, including performance curves and mechanical drawings, essential for design-in by HVAC engineers.
• Datasheet: LWBA2D250-092NT-15: This document provides all performance data, electrical specifications, and dimensional drawings for the 250mm model, required by procurement managers for part qualification.

Why Longwell for This Application

OEMs creating standardized HVAC equipment platforms require component partners that offer more than just a product. Longwell’s approach to developing this fan series addressed key procurement and supply chain challenges:

• Rapid Standardization for OEM Agility: A new standard product line from a European supplier typically runs 12–18 months from concept to catalog. Longwell’s NPI process compresses that significantly—definition, engineering, and full documentation happen in a fraction of the time. For an OEM trying to get a new platform out the door, that’s the difference between leading a market window and chasing it.
• Significant BOM Cost Reduction: These fans were engineered to match the air performance of premium European brands at a price point roughly 35–38% lower.
• Streamlined European Market Access: Both models ship CE-marked, with the technical file covering EN 60335-1 and performance testing per ISO 5801. The OEM isn’t left running a separate certification project or absorbing that risk. It shortens the path to market for equipment destined for the EU, and it removes a layer of regulatory drag that slows down a lot of launches.
• Verified Performance Data: Longwell fan data is based on tests conducted according to AMCA 210-16 and ISO 5801 standards.

Explore our full Backward Curved Centrifugal Fans range.

Frequently Asked Questions

Q: Can the LWBA2D250-092NT-15 be speed controlled?

A: No, this is a fixed-speed AC induction motor designed for 380 VAC, 50 Hz operation at approximately 2500 RPM. But if you have the specific need for fan speed control, the product can be customized by LONGWELL.

Q: What is the expected L10 lifetime in a -30°C environment?

A: The L10 life expectancy is rated at 30,000 hours at a reference ambient temperature of 40°C. Operation at the lower end of the temperature range, such as -30°C, does not negatively impact the life of the maintenance-free ball bearings. The fan is fully validated for continuous operation from -30°C to +60°C.

Q: Is the IP54 rating on the LWBA2D225 model sufficient for an outdoor air handling unit?

A: An IP54 rating provides protection against dust ingress and splashing water from any direction. This is typically sufficient for fans installed inside the weatherproof enclosure of an AHU or in a sheltered outdoor location. If the fan itself will be directly exposed to harsh weather, a model with an IP55 or higher rating would be recommended.

Project Item: 7057958821-LWBA2D225-092NT-11 / LWBA2D250-092NT-15
Project Date: 2026-07-25 01:24:47