Representative image of the series — dimensions and configuration of this model are given in the drawing and data table below.

ImpellerØ355 mm14.0 in
Max airflow3,467 m³/h2,041 CFM
Voltage110-120 V
Speed2,800 rpm
Input power659 W
Noise67 dB(A)

LWDE-355 (14″)U-MWN-03 EC Ultra Silent Metal Duct Fan Ø355 mm

Ø355 mm | EC | Max airflow 3,467 m³/h | 67 dB(A)

SKU: LWDE-355 (14")U-MWN-03 Categories: Impeller Ø200–400 mm, Inline Duct Fans, Ultra Silent Duct Fans

Direct from LONGWELL
OEM / ODM
Samples in 1–3 days
Production 15–30 days
12-month warranty
CE · RoHS · ETL on request

PDFRequest datasheetsent by an engineer within 1 business day

All files for LWDE-355 (14")U-MWN-031 files · direct download

CAD models (STEP / DWG) are released on request — see “Engineering files” below. Another format or a non-standard variant? Ask an engineer · download center

Used in

Central ventilation units Building & agricultural ventilation Vertical farming All industries →

Proven in projects

Smart home ERV Range hoods, ovens & fan coils Drying, heat treatment & ovens All case studies →

Get a quote · LWDE-355 (14")U-MWN-03

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WhatsApp / Phone+86 183 5827 4663 E-mail an engineersales@longwellfans.com Files for LWDE-355 (14")U-MWN-03datasheet · catalogue · drawings · curves — listed above

Samples 1–3 days · fee credited to your order
Typically 50–200 pcs · ~30 pcs for a first validation order
T/T 30 / 70 · FOB / CIF / DDP
Released to LONGWELL standards · 12-month warranty
How ordering works →

Dimensional drawing LWDE-355 (14")U-MWN-03

LWDE-355 (14")U-MWN-03 Dimensional drawing — **Dimensional drawing**Dimensions in mm. Confirm against the final approval drawing before machining cut-outs.

Files for LWDE-355 (14")U-MWN-03: datasheet, catalogue and drawing PDFs are listed above ↑ · CAD (STEP / DWG) on request — ask an engineer.

Technical description LWDE-355 (14")U-MWN-03

LWDE-355 (14")U-MWN-03 is a LONGWELL EC Ultra Silent Metal Duct Fan from the Ultra Silent Duct Fans range, impeller Ø355 mm, rated 110-120 V EC, maximum airflow 3,467 m³/h, noise 67 dB(A), input power 659 W. The EC motor integrates the drive electronics: stepless speed control by 0–10 V or PWM signal, speed feedback and high efficiency at part load.

Technical data

Model	LWDE-355 (14")U-MWN-03
Series	LWDE355
Motor type	EC
Phase	1-phase
Rated voltage	110-120 V
Frequency	60 Hz
Input power	659 W
Speed	2,800 rpm
Max. airflow	3,467 m³/h
Noise	67 dB(A)
Impeller diameter	Ø355 mm
Inlet diameter	355mm

Typical applications

Residential and commercial fresh-air systems
Kitchen and bathroom exhaust
Local pressurisation and booster duty
Hotel and office ventilation

Series LWDE355: models in the same series share the impeller and motor platform and differ in speed grade, voltage or lead-out / terminal-box configuration — compare them in the table below or ask for the best fit at your duty point.

Nameplate values: maximum airflow is measured at zero static pressure and maximum static pressure at zero airflow; the two never occur together. Confirm the operating point on the performance curve. Final selection is subject to the duty point (airflow / static pressure / voltage / control mode) and project verification.

Company certificates

Scans of original documents held by Ningbo Longwell Electric Technology Co., Ltd.: the company ISO 9001 / 14001 / 45001 management-system certificate. Click a scan to open the original.

ISO 9001 / 14001 / 45001Management systems of Ningbo Longwell Electric Technology Co., Ltd. (company certificate).

ISO 9001 / 14001 / 45001 management system certificate — LONGWELL certificate

PDFISO 9001 / 14001 / 45001 management system certificate

Need a Declaration of Conformity for this model and your destination market? Ask us — we arrange additional certification on request.

How to order LWDE-355 (14")U-MWN-03

Most first orders follow the same eight steps. Quantities, terms and lead times are confirmed in your quotation.

1SelectFind models by duty point in the selector or by model number, compare on the curve and add them to your RFQ list.
2Engineering checkWithin 1 business day you receive the duty-point check on the curve, price and lead time.
3SamplesStock models ship in 1–3 days.
4Validation supportDatasheets, drawings, wiring diagrams and DoC per model; test reports, CAD and register maps after a short project check or NDA.
5Order & paymentProforma invoice; first orders on T/T 30 / 70.
6Production & release15–30 days at the partner factory that builds your model, then inspected and released to LONGWELL standards with outgoing sampling to AQL 2.5.
7ShippingFOB / CIF / DDP by sea from Ningbo or Shanghai; express and air on EXW / FCA / DAP.
8After-sales12 months standard, extendable to 18–24 months by project agreement; test records retained for 5 years; 8D closed-loop for any issue; annual technical review for framework customers.

See terms, QC and FAQ →

Test & release at LONGWELL

Specified and drawn by LONGWELL; built to LONGWELL drawings by qualified partner factories; inspected and released to LONGWELL standards before shipment.

See test and release photos (8)

LONGWELL Semi-anechoic chamber — Semi-anechoic chamber

LONGWELL Test laboratory — Test laboratory

Test labs and all certificate scans →

Alternatives with the same impeller (Ø355 mm · EC)

Same impeller, different speed grade, power or wiring. Step up for more airflow, step down for lower noise.

Model	Max airflow	Max static pressure	Speed	Power	Noise	Voltage
LWDE-355 (14")U-MWN-03 this model	3,467 m³/h	see curve	2,800 rpm	659 W	67 dB(A)	110-120 V
LWDE-355 (14")S-MWN-04	6,200 m³/h	see curve	2,800 rpm	659 W	67 dB(A)	220-240 V	View