Low-noise fans: drop speed first, then choose the impeller
Fan noise climbs steeply with speed, so the first move is shifting the operating point to a lower speed; for the same airflow, a larger impeller running slower is always quieter than a small one spun up.
Noise is the most common complaint in ventilation systems, yet it is rarely the fan alone. The same fan can measure 5–10 dB(A) above nameplate with a blocked inlet, a jet aimed at sheet metal, or a resonant bracket. So the selection order is: shortlist 2–3 models by airflow and static pressure → compare noise at the actual duty → then confirm the installation preserves it.
Selection points
- Same airflow, bigger wheel: a larger impeller reaches the same airflow at lower speed, and noise follows the speed down.
- Avoid throttling: cutting airflow with dampers raises noise; an EC model slows down electrically — quieter and more efficient.
- Keep inlet and outlet clear: at least one impeller diameter of free space on the inlet side, no hard obstacle facing the outlet.
- Isolate vibration: soft mounts between fan and cabinet suppress the low-frequency hum of resonating sheet metal.
Model comparison
| Model | Airflow | Max static pressure | Power | Noise | Voltage |
|---|---|---|---|---|---|
| SF146A-D092A0-02 | 1080 m³/h | 580 Pa | 180 W | 64±1 dB(A) | 310 V DC |
| SF146A-E092A1-01 | 860 m³/h | 515 Pa | 120 W | 60±1 dB(A) | 115 V AC |
| SF146A-E092A3-02 | 1080 m³/h | 580 Pa | 180 W | 64±1 dB(A) | 230 V AC |
| SF146A-E092A3-CA | 600 m³/h | 480 Pa | 180 W | 52±1 dB(A) | 230 V AC |
| SF146A-E092B1-02 | 960 m³/h | 580 Pa | 165 W | 62±1 dB(A) | 115 V AC |
| SF146A-E092B3-03 | 1180 m³/h | 700 Pa | 220 W | 68±1 dB(A) | 230 V AC |
| SF146D-E092A1-01 | 860 m³/h | 515 Pa | 120 W | 60±1 dB(A) | 115 V AC |
| SF146D-E092A1-02 | 1050 m³/h | 585 Pa | 165 W | 62±1 dB(A) | 115 V AC |
| SF146D-E092A3-01 | 860 m³/h | 515 Pa | 120 W | 60±1 dB(A) | 230 V AC |
| SF146D-E092A3-02 | 1020 m³/h | 515 Pa | 165 W | 62±1 dB(A) | 230 V AC |
Specs are taken from each model's product page — full curves, dimension drawings and certificates live on the model pages. Models not listed can be browsed by series in the product catalogue.
Frequently asked questions
Under what conditions is the nameplate noise measured?
Typically as the A-weighted sound pressure level measured 1 m from the inlet, free inlet, rated voltage and rated speed. Installed in equipment, duct resistance and reflections usually push field readings higher.
How do I cut noise without giving up airflow?
First choose a larger, slower impeller for the same airflow; then move the operating point off full speed with EC control; finally treat the installation (clearance, isolation, attenuation). Stuffing in acoustic foam alone raises system resistance and can push speed — and noise — back up.
Which low-noise models are available?
The table below lists representative models from each series sorted by nameplate noise, low to high, with airflow and static pressure alongside; for a specific duty, our engineers can confirm the best pick.