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AC Infinity

AC Infinity CLOUDLINE PRO S4, Quiet 4” Inline Duct Fan with Speed Controller – EC Motor Ventilation Exhaust Fan for Heating Cooling Booster, Grow Tents, Hydroponics

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Availability: 15 left in stock
Fulfilled by Amazon
Arrives Saturday, May 30
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Size: 4-Inch


Color: Pro Speed Controller


Features

  • Designed to ventilate grow tents, transfer heating/cooling to rooms, circulate air, exhaust odors, and cool AV racks.
  • Features a wired 10-speed fan controller; also compatible with all UIS controllers with intelligent programming.
  • PWM-controlled EC motor provides quiet and energy-efficient performance with minimal heat and noise.
  • Mixed flow design with stator blade and hydrodynamic wind circles enables airflow delivery in high resistance areas.
  • Duct Size: 4 | Dimensions: 6.9 x 11.9 x 7.4 in. | Airflow: 205 CFM | Noise: 28 dBA | Bearings: Dual Ball

Brand: AC Infinity


Color: Pro Speed Controller


Electric fan design: Exhaust Fan


Power Source: Corded Electric


Style: Modern


Product Dimensions: 6.9"D x 7.4"W x 11.9"H


Room Type: Bathroom, Kitchen


Special Feature: Bladeless


Recommended Uses For Product: Air Circulation, Cooling


Mounting Type: Wall Mount/Ceiling Mount


Power Source: Corded Electric


Room Type: Bathroom, Kitchen


Special Features: Bladeless


Recommended Uses For Product: Air Circulation, Cooling


Mounting Type: Wall Mount/Ceiling Mount


Controller Type: Button Control,Remote Control,App Control


Number of Speeds: 8


Noise Level: 28 Decibels


Wattage: 21 watts


Number of Blades: 10


Air Flow Capacity: 205 Cubic Feet Per Minute


Speed: 2800 RPM


Voltage: 240 Volts


Indoor Outdoor Usage: Indoor


Control Method: App


Standby Power Shutoff: High


Is Product Cordless: No


Number of Power Levels: 10


Material: Polycarbonate


Blade Material: Plastic


Color: Pro Speed Controller


Electric Fan Design: Exhaust Fan


Style: Modern


Finish Type: Matte


Collection Name: Channel Fans


Item Dimensions D x W x H: 6.9"D x 7.4"W x 11.9"H


Blade Length: 7.4 Inches


Item Weight: 2.61 Kilograms


Cable Length: 144 Inches


Brand Name: AC Infinity


Included Components: Cord, Remote


Model Name: CLOUDLINE S4


Model Number: CLOUDLINE S4


Manufacturer: AC Infinity


UPC: 819137020290


Global Trade Identification Number: 90


Unit Count: 1.0 Count


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, May 30

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

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View our full returns policy here.

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Top Amazon Reviews

    • The Rolls-Royce of exhaust fans
Size: 4-Inch Color: Pro Speed Controller
This is my third, and likely last, exhaust fan I've bought for a project. I wanted an exhaust system for our cat's litter box cabinet so that it would create a small amount of negative pressure and pull the bad odors outside. This fan is absolutely perfect in every possible way and has far exceeded my expectations. I arrived at this fan, after purchasing two others that were just too loud, as the noise seemed to bother the cat. I installed 2" PVC in the wall behind where the cabinet is, because I needed something small enough to fit. I then had a 90 degree elbow coming out of the wall, through a cover plate and then going into the back of the cabinet. In the attic, I installed a 2" to 4" duct adapter onto the 2" pipe, ran 25' of flex duct to this fan, and then another 16' run of duct to the roof vent. While the first two fans where very noisy, even at the lowest speeds, this one is virtually silent. I'm running it on level 2 and cannot hear anything inside the cabinet or in the house. Since I'm restricting the intake to only 2", anything above level 2 would likely just be a waste of power. This setup is working perfectly and creates more than enough exhaust to do the job and it does it in silence. The prior fans moved the air ok but had a really annoying hum that could be heard through the ductwork and also inside the house through the insulated ceiling. I hear nothing with this one. In addition to the above, the fan is rock solid and came with EVERYTHING one could possibly need to install it, including hose clamps. It's almost overkill but shows attention to detail. It also came with a very nice instruction book (yes, it's a substantial book) with detailed instructions on every aspect of installation and operation. The speed controller is very nice and easy to use. I just set it to my desired level and forget it. It will remember its current setting and resume after a power outage. This fan cost a bit more but is absolutely worth every penny paid. The difference in quality and quietness cannot be matched. I could not be happier, cat is happy, and we have an odor-free home. ... show more
Reviewed in the United States on December 8, 2023 by R. Precourt
    • Used it to Boost the Exhaust of a Falcon A1 Laser Engraver
Size: 4-Inch Color: Pro Speed Controller
Review Image by marktrimarc
Review Image by marktrimarc
The media could not be loaded. This review is for the 4" version of the AC Infinity CLOUDLINE PRO, also known as the S4. My son had received a Falcon A1 Laser Engraver from his wife for Christmas and I offered to create a custom exhaust setup for it. They have a young child and what I had read about the possible toxicity of laser engraving fumes (specifically for leather cutting and engraving) motivated me to get the fumes completely out of their house and garage. After a few hours of research, I zeroed in on this CLOUDLINE PRO S4 for the task, as well as some 4" flexible duct and a silicone elbow/reducer (4" to 3", also found on Amazon). I was not disappointed with the results! See my two photos. I'm very methodical and careful, so it took me a few hours to complete the system, but most of that time was spent sawing through the garage drywall and configuring the termination of the duct at the roof's soffit. My observations: The inline fan is fairly big, but lightweight and is very easy to secure to the wall with the included mounting bracket. It's very quiet! The ten-speed variable control will take it from too quiet to hear, up to a whisper, and finally to a slight swooshing sound at full speed. I was impressed with the air volume it moved. I could definitely feel the air coming from the outlet outside. It reminded me of the volume of air a clothes dryer would produce. Sure enough, with a rating of 205 cfm (likely measured without ductwork), this fan compares to the average clothes dryer exhaust of 150 - 200 cfm. A bonus for the setup I installed is that garages are very leaky and exhausting this much air will bring a similar amount of outside air as "makeup air" and will create a cooling effect for the garage when it's hotter inside than outside. Everything I read online indicated that AC Infinity made good quality inline fans and I got the same impression working with it. Even the packaging and "presentation" upon opening it was far nicer than I had expected. I would definitely buy this brand of inline fan again the next time I need this type of ventilation. ... show more
Reviewed in the United States on February 1, 2026 by marktrimarc
    • AC Infinity CLOUDLINE PRO S6 – Quiet and Powerful Cooling for My Miner Room
Size: 6-Inch Color: Pro Speed Controller
I purchased the AC Infinity CLOUDLINE PRO S6, 6” Inline Duct Fan with Speed Controller to help keep my miner room cool, and it has exceeded expectations. The EC motor is both powerful and efficient, and what surprised me most is just how quiet it runs, even at higher speeds. Installation was straightforward, and the included speed controller makes it easy to adjust airflow as needed. Running multiple miners can heat up a room quickly, but this fan has made a huge difference — it keeps temps under control without adding a lot of noise or power draw. The build quality feels premium, and I can tell it’s designed to run continuously without issues. ✅ Pros: Very quiet operation, even at high speeds Strong airflow to keep miner room temperatures down Speed controller included for precise adjustment Efficient EC motor saves power over time Solid build quality, designed for 24/7 use ❌ Cons: Higher upfront cost compared to budget inline fans Speed controller cable could be a little longer 💡 Tips: Use insulated ducting to further reduce noise. Mount the fan with vibration-dampening straps for an even quieter setup. Pair it with a temperature or humidity controller for automatic adjustments. Clean the fan and ducts periodically to maintain peak airflow. Bottom Line: The CLOUDLINE PRO S6 is a top-tier ventilation fan that’s perfect for high-demand environments like mining rooms, hydroponics, or grow tents. It’s quiet, efficient, and powerful — exactly what you need for reliable cooling in a 24/7 setup. ... show more
Reviewed in the United States on August 25, 2025 by Kenny Campbell

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