Best fans for a grow box: EC or AC?

Are you interested in the main differences between EC fans and AC fans? Then read this article, in which we will not only explain them but also show why, from a professional point of view, it usually pays to invest a bit more in a high-quality fan equipped with an electronically commutated DC motor (EC motor). We will also recommend proven products. Every experienced indoor grower knows well that ventilation equipment that combines features such as long service life, quiet operation and low electricity consumption is an investment that pays back with every subsequent harvest.

While AC fans, driven by asynchronous electric motors with a traditional design, are generally used more for occasional ventilation of the cultivation space, EC fans operate much more efficiently, and therefore in practice you can use them far more to continuously ensure ideal conditions for vigorous development of your plants thanks to a perfect microclimate inside the grow tent or room throughout the entire cultivation cycle.

Advantages of EC fans

• Many times longer lifespan
• Significantly lower operating costs (energy efficiency savings)
• Low noise and zero hum even at low speeds
• Smaller size for the same performance
• Simple and precise power control using digital controllers without reducing lifespan

OUR TIP: Discover the leader in speed control! Use controllers from the top Dutch manufacturer TechGrow.

In the picture on the right you can see one of the best-selling speed controllers for fans by TechGrow.

EC controls for EC fans:

• GSE controller with LCD display for 2 EC fans

This digital controller from a renowned German manufacturer was made exclusively for EC fans. It allows up to 15 individual settings using only 3 buttons and easy regulation depending on temperature, humidity, day phase and hysteresis. Technically it is also equipped with a clear LCD display and an integrated light sensor.

• A simpler and cheaper alternative is the proven GSE controller for EC fans.

How do EC motors work?

Electronically commutated DC motors, which are classified among synchronous motors, feature a so-called commutation circuit — an electronic speed control system that keeps the fan at optimal RPM. EC motor consists of a stator and a rotor fitted with permanent magnets made of ferrite material. The rotor and stator each create their own magnetic field. These fields interact and produce torque on the rotor. The rotor speed in these synchronous motors is therefore identical to the rotational speed of the electromagnetic field. As a result, there are no slip losses typical for asynchronous (AC) motors, where the electromagnetic field rotates faster than the rotor. (For AC motors slip is necessary, otherwise no torque would be generated.)

Prima Klima fans with EC motor

The control electronics including connectors and the capacitor form a single compact unit in these fans, made in Germany, protected by an impact-resistant and non-flammable nylon housing.

OUR TIP: If you are considering buying an EC fan and are interested in the best efficiency on the market, you can jump straight to the separate article about the professional WHISPERBLOWER fans, which are virtually unrivalled in this respect.

Prima Klima fans are manufactured in the Czech Republic to German quality standards. That is why they have long been among growers' favorites on the market, whether we are talking about the more efficient models fitted with synchronous (EC) motors, or the cheaper Prima Klima fans with lower efficiency and shorter lifespan driven by an asynchronous (AC) motor.

Therefore, in cooperation with our experts and based on customer experience, we selected a few key models outside the WHISPERBLOWER series:

• A small but highly efficient centrifugal inline fan with improved aerodynamic shape is, for example, the Prima Klima PK160EC-TC. This quality fan with thermostat is powered by a premium motor from ZIEHL-ABEGG with a backward-curved rotor blade design.
• The long-time best-selling EC fan from the popular Prima Klima brand is the star labeled PK125EC-TC, with an airflow capacity of 680 m3/h. This EC fan also features a thermostat, allowing users to conveniently control the temperature in the cultivation space.

• More than double the airflow capacity is offered by another long-time bestseller in Prima Klima's inline EC fan category, the PK250EC-TC, which allows both speed and temperature control.

• The premium BLUE LINE range is fitted with ECblue motors from Ziehl-Abegg, which are subjected during development and production to the strictest tests, whether for ingress protection (IP) rating or increased humidity. An example is a model that pairs well with the ECO K2607 filter together with combiflex ducting or the quiet sonoflex duct and hose clamps. For large commercial operations, the extremely powerful large fans with 8000 m3/h airflow are a fantastic fit.

Silenced EC fans from the Q-Max series by Can-Fan RUCK

The main added value of these reliable and high-quality EC fans is undoubtedly their discreet operation.

It would be a shame not to present at least two of the best-selling models from this silenced series in the context of EC fans. They differ in airflow capacity, while both axial fans offer absolutely the highest aerodynamic efficiency and unbeatable electricity consumption thanks to the new 3D rotor and stator:

• Silenced Q-Max EC fan 2000 m3/h, 250 mm
• Silenced Q-Max EC fan 3247 m3/h, 355 mm

Besides the incredibly quiet operation, which is the result of perfect acoustic insulation of the metal housing, these fans also offer other advantages:

• High performance and long service life.
• Smooth airflow without turbulence.
• EC motor speed controller.
• Easy installation thanks to integrated mounting brackets.

You will achieve the best results in a grow box by combining them with Can-Filters. Can-Fan RUCK EC fans can also be perfectly combined with these original controllers from the same manufacturer:

• Can-Fan EC temperature and speed controller
• LCD EC Can Fan controller regulator otacek EC ventilatoru

We hope this article helped you decode the most common questions and that you now have a better idea which type of fan is right for you — whether it's worth buying an EC fan or whether an AC fan will suffice. We enjoy your questions, so do not hesitate to ask us anything at the well-known email address info@higarden.cz. We're here for you!

We also recommend these products:

• Fan PRIMA KLIMA EC WHISPERSBLOWER 450m3/h, 125mm, EC motor with smooth regulation PK125-WHSP-ESM
• Fan PRIMA KLIMA 800m3/h, 160mm, with thermal control (PK160-TC)
• Garden High PRO - PROFAN TT 125mm, 220-280m3/h, 2 speeds

Further reading:

• How strong a fan do you need?
• Prima Klima CARBOCONE: innovative activated carbon filters
• Differences between axial and radial fans. What and why?