Question 1

What are the advantages of an EC double inlet centrifugal blower compared with a single inlet blower?

Accepted Answer

The EC double inlet centrifugal blower delivers greater airflow and higher static pressure because it draws in air from both sides, and when the motor is positioned in the center of the impeller it provides good impeller dynamic balance. The EC single inlet blower draws in air from only one side, which makes its structure more compact and requires less installation space, so users should choose according to the specific application scenario.

Question 2

Is the volute of the Duct Fan made of metal or plastic?

Accepted Answer

Both metal and plastic volutes are available, and both impeller types can be provided.

Question 3

Can EC Duct Fans provide wide voltage, for example, can they be used within the 110-240VAC range?

Accepted Answer

A wide-voltage version of the EC Duct Fan is available. Please contact our sales team.

Question 4

We are currently using an AC Duct Fan and do not want to change the existing installation dimensions. Can we replace it with your company's EC Duct Fan?

Accepted Answer

Yes, our company's EC Duct Fan installation dimensions are compatible with those of AC Duct Fans. This compatibility means that when replacing or upgrading from an AC Duct Fan to an EC Duct Fan, the existing mounting holes, duct connections, and overall installation clearances can typically be reused without modification. As a result, the swap is straightforward and does not require additional adapters or rework of the ductwork or mounting structure.

Question 5

Why does the modern greenhouse planting industry choose EC Fan Unit components?

Accepted Answer

EC Fan Units reduce energy consumption and costs, enable precise climate regulation, and enhance crop yield and quality, directly addressing growers' core demands for profitability and production stability. The adoption of EC Fan Units in modern greenhouse cultivation is driven primarily by their high energy efficiency and precise environmental control capabilities, which directly impact cultivation profitability and crop quality consistency. Compared with traditional AC fans, EC fans offer fundamental differences in energy efficiency, controllability, and reliability. Choosing an EC Fan Unit is not merely an equipment upgrade but a critical step in the transition toward refined and intelligent management in modern greenhouse cultivation.

Question 6

Why can selecting EC centrifugal fans significantly reduce operating costs?

Accepted Answer

EC fans are more energy-efficient than traditional AC fans in HVAC ventilation systems. In the HVAC industry, ventilation system energy consumption can account for 70% of total operating costs, making energy efficiency the primary economic consideration. EC fans (Electronically Commutated) utilize permanent magnet synchronous motors (PMSM) and built-in digital controllers, fundamentally eliminating brush wear, commutator losses, and slip resistance associated with traditional AC motors. This structural difference delivers significant efficiency advantages:
1. Higher rated efficiency: EC fans can achieve efficiency above 90%, while traditional AC fans typically range between 55–70%.
2. Substantial advantage at partial load: Greenhouse ventilation demand varies with day-night cycles and seasons, and fans operate under partial load for most of the time. Traditional AC motors experience a sharp efficiency drop to 40–55% when operating below design speed, whereas EC motors maintain high efficiency across the full speed range. In actual projects, some farms have reduced monthly electricity costs by 35% by switching to EC fan systems.

Question 7

What is EC duct fan?What “EC” means?

Accepted Answer

An EC duct fan uses an EC (electronically commutated) motor instead of a traditional AC induction motor, and is a duct-mounted ventilation fan.

In short: it is the high-efficiency, variable-speed version of a standard duct fan.
EC = electronically commutated.
It is essentially a brushless DC motor (BLDC) with built-in power electronics. The motor can often run directly from AC mains, such as 230 V single-phase, because it internally converts AC to DC and then uses electronic commutation to drive the motor coils.
So an EC duct fan is not just a fan with a different blade — the motor and control electronics are the key difference.

Question 8

Comparison of the pros and cons of four types of fans (Inline, Oscillating, Clip-on, Centrifugal fan) in the hydroponic growing industry?

Accepted Answer

Inline fans are best suited for overall exhaust in grow tents or rooms, delivering a good balance of airflow (CFM) and medium static pressure with easy installation in ductwork. However, their performance drops when facing high resistance (such as carbon filters), so they are typically connected to carbon filters and ductwork as the primary exhaust solution.

2. Oscillating Fan: Canopy Circulation, coverage area, gentle airflow, wide coverage, breaks leaf boundary layer, simulates natural wind, dispersed airflow, cannot be used for long-distance exhaust, canopy circulation in medium to large grow spaces, prevents localized temperature and humidity imbalances.

3. Clip-on Fan: Targeted Airflow, flexibility, adjustable airflow, compact size, flexible installation, low energy consumption; concentrated airflow, limited coverage, only suitable for localized circulation, small tents, propagation areas, mother plant areas, or as supplementary circulation in large spaces.

4. EC Centrifugal Fan: High Static Pressure, high static pressure, extremely high static pressure, can push air through complex ductwork and filters; compact size, low power consumption, suitable for large-scale commercial cultivation, multi-layer vertical farms, long duct runs, or high-density carbon filter systems.

Question 9

How can Inline, Oscillating, Clip-on, and Centrifugal fans be comprehensively combined for use in retrofitting indoor growing facilities?

Accepted Answer

A high-performance EC Inline or EC Centrifugal Fan Unit should be used as the primary exhaust fan, responsible for air exchange throughout the entire space. Use one or more Oscillating Fans for canopy circulation to ensure all plants receive gentle airflow. Use Clip-on Fans as a supplement to address local dead zones or provide targeted airflow for specific areas. **Summary: Negative pressure control and odor management: Ensure the exhaust airflow is slightly greater than the intake airflow to maintain a slight negative pressure in the grow space, so that all air is expelled through the activated carbon filter, effectively controlling odors; Filter placement: Install the activated carbon filter on the intake side of the fan to keep the fan clean and reduce noise.

Question 10

What to check when selecting one EC Duct Fan?

Accepted Answer

Duct diameter, airflow (m³/h or CFM), static pressure (Pa or in. WG), voltage and phase, control signal (0–10 V, PWM, Modbus, etc.), noise level (dB(A)), IP rating and ambient temperature, and certifications and local electrical codes are the key specifications to confirm when selecting a fan.

Question 11

What are the advantages of EC Duct Fan?

Accepted Answer

An EC duct fan is a duct-mounted fan powered by an electronically commutated motor that delivers better efficiency, smoother speed control, lower noise, and smarter integration than a conventional AC duct fan — at a higher initial cost.

Question 12

What are the main applications of EC duct fans in?

Accepted Answer

HVAC supply and exhaust systems, bathroom, toilet, and kitchen ventilation, cleanrooms and laboratories, heat recovery ventilation (HRV/ERV), grow rooms and agricultural ventilation, industrial ducted exhaust, and radon mitigation and general air movement are the applications covered by this guide.

Question 13

Why do EC Duct Fans adopt EC external rotor motors + backward curved centrifugal fans?

Accepted Answer

The EC Duct Fan adopts an EC external rotor motor combined with a backward-curved centrifugal impeller, which is currently one of the most ideal combinations for duct fans in terms of balancing energy efficiency and performance. This design simultaneously achieves high static pressure, high efficiency, low noise, compact structure, wide-range speed control, and intelligent control under high-resistance duct conditions.

Question 14

Why is the combination of an EC external rotor motor and a backward curved centrifugal fan the optimal solution?

Accepted Answer

The EC external rotor motor with a directly mounted backward-curved centrifugal impeller eliminates belts, gears, and couplings, achieving virtually zero transmission loss. Overall efficiency = motor efficiency × aerodynamic efficiency. Both are high, so system efficiency is naturally superior.

2. High static pressure + adjustable speed to adapt to duct resistance changes
Duct system resistance varies with filter clogging, damper position, and network balancing. EC motors offer stepless speed control, and backward-curved impellers remain highly efficient at high static pressures, enabling:
Constant air volume control: automatically increases speed as resistance rises to maintain constant airflow
Constant pressure control: maintains stable duct static pressure
Demand-based ventilation: reduces speed at low loads for significant energy savings

3. Compact and lightweight, suitable for duct installation
The external rotor motor has a short axial length, and the backward-curved centrifugal impeller can be designed in a compact form. The overall unit is small and can be installed directly into round or rectangular ducts, saving installation space.

4. Low noise for improved comfort
EC motors are inherently low-noise, and backward-curved impellers provide smooth airflow. The combination results in overall noise levels far lower than AC forward-curved multi-blade fans, making them suitable for noise-sensitive environments such as hospitals, laboratories, data centers, and residential buildings.

5. Intelligent control and system integration
EC motors have built-in electronic drives and can easily connect to 0–10V, Modbus, and BMS for remote monitoring, fault alarms, and energy consumption statistics. The self-power-limiting characteristic of the backward-curved impeller prevents the motor from overload and burnout even under abnormal operating conditions.

6. Long service life, low maintenance
No carbon brushes, no belts, no mechanical commutation—long bearing life and extremely low maintenance costs. The backward-curved impeller resists dust accumulation, minimizing performance degradation over long-term operation.

Question 15

How noisy is the DG120 series?

Accepted Answer

Rated noise across the DG120 series spans 56–61 dB(A) depending on model and size. Because noise follows speed, the easiest way to reduce sound levels is to choose a smaller model at a lower speed for the same airflow, or a speed-controlled EC/DC version where available — ideal for noise-sensitive environments such as offices, laboratories and residential ventilation.

Question 16

What bearings do DG120 fans use, and how long do they last?

Accepted Answer

Models in the DG120 series use NSK ball bearings, which supports continuous-duty operation in HVAC and industrial ventilation. Bearing life depends mainly on operating speed and temperature: keeping inlet air clean, avoiding vibration and running at moderate speeds maximise service life. For an L10 life estimate at your exact operating point, contact our engineering team.

Question 17

Are DG120 fans suitable for dusty or outdoor environments?

Accepted Answer

Protection classes in the DG120 series include IP44. Models rated IP44 seal the motor against dust and splashing water for typical industrial environments; for outdoor or wash-down installations, choose the highest IP rating available in the series and avoid direct high-pressure water jets. The standard operating temperature range is -25 °C ~ +60 °C.

Question 18

How do I choose the right DG120 model?

Accepted Answer

Start from the airflow you need — the DG120 series covers 300–380 m³/h. In this series, EC models offer stepless speed control and the best efficiency at partial load. The comparison table on this page lists airflow, voltage, power and noise for every model, or send us your operating point (airflow and static pressure) and our engineers will size the right model for you.

Question 19

What is the MOQ, lead time and sampling policy for DG120 fans?

Accepted Answer

Standard MOQ is 192 PCS per model, with a typical lead time of 25-30 days. Samples are available for evaluation before volume orders. OEM/ODM customization — private labels, connectors and speed curves — is supported at our Foshan factory.

Question 20

How noisy is the DG140 series?

Accepted Answer

Rated noise across the DG140 series spans 59–66 dB(A) depending on model and size. Because noise follows speed, the easiest way to reduce sound levels is to choose a smaller model at a lower speed for the same airflow, or a speed-controlled EC/DC version where available — ideal for noise-sensitive environments such as offices, laboratories and residential ventilation.