AC Infinity CLOUDLINE PRO S4 Review: Quiet 4” Inline Duct Fan

Welcome to my review of the AC Infinity CLOUDLINE PRO S4, the quiet 4” inline duct fan with speed controller. I’ve been using this fan in my home for a while now, and I’m excited to share my experiences with you.


Pros and Cons

What We Liked

  • This fan is incredibly quiet, making it perfect for use in bedrooms or other noise-sensitive areas. I can barely hear it running even at higher speeds.
  • The speed controller is a great feature, allowing you to easily adjust the fan’s airflow to suit your needs. It’s convenient and user-friendly.
  • The energy-efficient performance of the PWM-controlled EC motor is impressive. It doesn’t generate much heat or noise, which is a huge plus.
  • The mixed flow design of the fan enables efficient airflow delivery even in high-resistance areas. It’s great for venting grow tents and transferring heating/cooling to different spaces in my home.
  • The build quality of this fan is top-notch. It feels solid and durable, and I have no doubt that it will last for a long time.

What Can Be Improved

  • Although the fan is advertised as having 8 speeds, mine actually has 10 speeds. This discrepancy might cause confusion for potential buyers.
  • The speed control could be improved. It takes a while to cycle through the speeds, and it would be more convenient to have separate buttons for power on/off and speed adjustments.

Quick Verdict

In conclusion, the AC Infinity CLOUDLINE PRO S4 is an excellent choice if you need a quiet and efficient inline duct fan. Its low noise level, energy-efficient performance, and adjustable airflow make it suitable for various applications, including grow tents and ventilation systems. The fan’s build quality is impressive, and it has exceeded my expectations in terms of durability and performance. If you’re in need of a reliable and quiet inline duct fan, I highly recommend considering the AC Infinity CLOUDLINE PRO S4.

Check out the AC Infinity CLOUDLINE PRO S4 for yourself on Amazon!

Unboxing – What’s Inside?

As an avid fan of AC Infinity products, I recently purchased the AC Infinity CLOUDLINE PRO S4 on Amazon. Living in the USA, I decided to buy this product as I needed a reliable and efficient ventilation exhaust fan for my grow tent. I was excited to test out this new addition to my setup and was pleased with how fast the delivery was, arriving at my doorstep within a couple of days.

Opening the box, I found the following items inside:

  • The AC Infinity CLOUDLINE PRO S4 exhaust fan
  • A speed controller for adjusting fan settings
  • Power cord for easy connection
  • Mounting hardware for secure installation
  • Instruction manual to guide me through the setup process
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The AC Infinity CLOUDLINE PRO S4 is a modern and sleek-looking exhaust fan designed by AC Infinity. It weighs 5.74 pounds and has a blade length of 7.4 inches. The fan operates with a voltage of 240 Volts (AC) and consumes 21 watts of power. With a noise level of only 28 dB, it ensures quiet operation. This fan is perfect for indoor use and can be controlled through the AC Infinity app. The matte finish gives it an elegant look.

Documentation/ User Guide

The user guide provided with the AC Infinity CLOUDLINE PRO S4 was incredibly helpful in setting up and configuring the fan. It provided clear and concise instructions on how to connect the fan, use the speed controller, and make the most out of its features. The user guide also included diagrams and visuals, making it easy to follow along. To access the user guide, you can click here.

Features – What We Found

Efficient Ventilation for Grow Tents and More

The AC Infinity CLOUDLINE PRO S4 is specifically designed for ventilating grow tents, transferring heating/cooling to rooms, circulating air, exhaust odors, and cooling AV racks. With its powerful airflow of 205 CFM, it ensures efficient ventilation, maintaining optimal conditions for plant growth in grow tents. It can also be used to transfer heating or cooling to other rooms, improving the overall climate control of your space.

Additionally, this inline duct fan is capable of circulating air effectively, eliminating stagnant air and promoting better air circulation. It can also exhaust odors, making it perfect for spaces where air quality needs to be improved. Furthermore, its ability to cool AV racks helps prevent electronics from overheating, ensuring their longevity and performance.

Pro-tip: When using the AC Infinity CLOUDLINE PRO S4 in a grow tent, place the fan near the top of the tent to help remove excess heat. This will create a temperature gradient that encourages proper air circulation and prevents heat pockets.

Convenient and Customizable Fan Control

The AC Infinity CLOUDLINE PRO S4 comes with a wired 10-speed fan controller that allows you to easily adjust the fan speed to your desired airflow and noise level. This gives you full control over the ventilation and ensures that you can create the ideal environment for your needs. The fan controller also features intelligent programming, making it compatible with all UIS controllers for advanced control options.

With the fan controller, you can easily switch between different fan speeds to optimize the airflow based on your specific requirements. Whether you need high-speed airflow for rapid cooling or a quieter operation for noise-sensitive environments, the fan controller allows you to conveniently customize the fan’s performance.

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Product Link: AC Infinity CLOUDLINE PRO S4

Quiet and Energy-Efficient Performance

The AC Infinity CLOUDLINE PRO S4 utilizes a PWM-controlled EC motor, which not only provides quiet operation but also ensures energy-efficient performance. The EC motor generates minimal heat and noise, allowing the fan to operate quietly without disturbing your environment. This is particularly beneficial in areas where noise needs to be minimized, such as bedrooms, offices, or recording studios.

The energy efficiency of the EC motor significantly reduces power consumption compared to traditional AC motors, resulting in cost savings and environmental benefits. The advanced motor technology ensures the fan operates efficiently while still delivering the necessary airflow to properly ventilate, cool, or circulate air in your space.

Mixed Flow Design for Enhanced Airflow Delivery

The AC Infinity CLOUDLINE PRO S4 features a mixed flow design, incorporating stator blades and hydrodynamic wind circles. This design allows for efficient and balanced airflow delivery even in high resistance areas. The stator blades help direct the airflow, while the hydrodynamic wind circles ensure that the air is distributed evenly to all parts of the space.

By enabling airflow delivery in high resistance areas, the mixed flow design increases the effectiveness of the fan in overcoming any obstructions or restrictions in the ventilation system. This ensures optimal air circulation and ventilation, preventing the formation of stagnant air pockets and promoting a healthier indoor environment.

Durable and Reliable Construction

The AC Infinity CLOUDLINE PRO S4 is built to last with its durable construction. It features dual ball bearings, known for their longevity and smooth operation. The dual ball bearings not only increase the fan’s lifespan but also contribute to its quiet operation.

With a duct size of 4 inches and compact dimensions of 6.9 x 11.9 x 7.4 inches, the fan can easily fit into various ventilation setups. Whether you’re using it in a grow tent, hydroponics system, or cooling AV racks, the AC Infinity CLOUDLINE PRO S4 provides a reliable and efficient ventilation solution.

Review and Scores

Our Score: 93.0

I recently purchased the AC Infinity CLOUDLINE PRO S4, and I have been extremely satisfied with its performance. This fan has exceeded my expectations in terms of both quietness and power. The sound level is minimal, allowing me to use it in various settings without causing any disturbance. It has been running smoothly for the past four years, and I have experienced no issues so far.

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One feature that stands out to me is the wired 10-speed fan controller. It offers excellent adjustability, allowing me to customize the airflow according to my specific needs. Additionally, I appreciate that it is compatible with other UIS controllers, which adds to its versatility. The energy efficiency of the PWM-controlled EC motor is impressive, ensuring minimal heat generation and noise output.

The mixed flow design of this fan, featuring a stator blade and hydrodynamic wind circles, enables efficient airflow delivery even in high-resistance areas. This has proven to be especially beneficial in my grow tent setup, where it effectively ventilates the space and maintains optimal conditions for plant growth. Overall, I highly recommend the AC Infinity CLOUDLINE PRO S4 to anyone in need of a reliable, quiet, and efficient ventilation solution.

Click here to buy the AC Infinity CLOUDLINE PRO S4 and experience its exceptional performance!

Similar Options

When it comes to finding the perfect inline duct fan for your ventilation needs, the AC Infinity CLOUDLINE PRO S4 may not be the only option worth considering. Here are a few alternative products that you should suggest to readers:

  1. AC Infinity CLOUDLINE PRO S4 – This is the main product that you have already mentioned. But if readers are looking for similar options, they can explore these alternatives as well.
  2. AC Infinity Air Carbon Filter 4 – For those who prioritize odor control in their grow tents or hydroponic systems, this carbon filter is a great addition to consider. It is designed to fit perfectly with inline duct fans, effectively eliminating unwanted smells and ensuring a fresh environment.
  3. TerraBloom 4 Inch Inline Fan ECMF-100 – If energy efficiency is a major concern for your readers, this fan with its premium metal casing and energy-efficient EC motor is an excellent option. The digital speed controller allows precise control over airflow, making it ideal for large spaces.
  4. AC Infinity Flexible 4-Inch Aluminum Ducting – To ensure proper ventilation and exhaust, heavy-duty four-layer protection is essential, and this aluminum ducting delivers just that. With a length of 8 feet, it is suitable for both heating and cooling purposes, providing flexibility and efficient airflow.

By suggesting these alternate products, readers can explore a range of options that meet their specific requirements and preferences. Whether it’s odor control, energy efficiency, or durability, each alternative product offers unique features that may better fulfill their needs. So, why limit oneself when there are multiple choices available to enhance their ventilation and grow tent setups?