A CLOSER LOOKHome Improvement
Air goes in below. Out to the side.
AC Infinity MULTIFAN S2
USB centrifugal blower
Buyer feedback ↓The MULTIFAN S2 uses a low, side-exhaust blower instead of the open front-to-back design of an ordinary USB fan. Its shape is the reason to choose it for a low-clearance shelf.
- 4.7 × 4.7 inFrame face · H × WProjecting feet excluded≈ 1.4 bank-card lengths per side
- 3 speedsInline controlOff, low, medium and high
- Side exhaustBlower layoutIntake underneath
Amazon US · USB centrifugal blower · Retailer link
THE QUICK TAKE
Is it right for you?
The S2 is a useful choice when a sideways outlet fits the space better than an upright axial fan. It draws air through the lower opening and pushes it through the rectangular side outlet. The included feet and speed switch make it easy to place on a firm indoor shelf.
Skip it if you cannot leave clearance under the intake and in front of the outlet. Putting the blower flat against a blocked surface defeats its design. It is an indoor electronics fan with a stated 35–85% operating humidity range, not a sealed unit for direct mist.
01 / BUYING NOTES
Before you buy.
Follow the outlet.
The rectangular opening is the exhaust. Aim that side toward the area needing circulation, and avoid putting a pot directly in front of it.
Leave the underside open.
The fan draws air through its lower intake. Keep the feet in place for a shelf installation and do not set it on soft fabric that can cover the opening.
Set speed at the cable.
The inline switch provides off and three speed levels. It does not sense temperature or humidity. Choose a speed for the actual position, rather than assuming the fastest setting is always better.
AC Infinity model specifications ↗ · MULTIFAN installation manual ↗ · Exact US package ↗
02 / AMAZON REVIEWS
The buyers’ view.
Owners using the S2 on audio receivers describe quiet operation at low speed. One particularly valued the side outlet for pushing trapped heat toward the open front of a media cabinet.
Long-term experience is less straightforward: an owner running it continuously inside a mini fridge reports that the first fan became noisy and failed after about six months, while its replacement remained quiet and ran for more than sixteen months.
What buyers like
- noise level253
- quality241
- performance158
- cooling performance151
- airflow107
- Value for money60
- fan speed control51
- build quality44
The small numbers are review mentions. Topics and sentiment are from Amazon’s customer-review overview.
Amazon US · Checked . Ratings may include other colors and sizes.
View source ↗03 / SOURCES
What the sources say.
The S2 uses a centrifugal layout with a side outlet, a physical speed selector and rubber feet. Its orientation is different from the straight-through airflow of the S1 and S3.
The installation guide calls for an unobstructed air path and distinguishes circulating air inside a cabinet from actually exhausting heat outside it. A fully closed cabinet cannot ventilate through a fan alone.
04 / COMPARE
Different priorities.
Choose the tradeoff that fits how you will use it.
Swipe to see every alternative →
THIS GUIDEAC Infinity MULTIFAN S2Single side-exhaust blower |  ALTERNATIVEAC Infinity MULTIFAN S3Single guarded fan |  ALTERNATIVEAC Infinity MULTIFAN MiniSingle miniature fan | |
|---|---|---|---|
| Amazon price | $17.99 | $15.99 | $15.99 |
| Best for | A low shelf with a sideways air path | General shelf circulation | A very small local gap |
| Design | Centrifugal blower | Guarded axial fan | Miniature guarded axial fan |
| Use | Keep lower intake and side outlet clear | Allow an open path through both sides | Keep both grilles clear |
| Consider | Needs clearance below the body | Larger frame than the Mini | Limited reach across a large shelf |
| Explore | Read buying guide →Amazon source ↗ | Read buying guide →Amazon source ↗ | Read buying guide →Amazon source ↗ |
About these everyday comparisons
Approximate comparisons to familiar objects: a bank card’s 3.37-inch long edge, a Letter sheet’s 11-inch long edge, or a US nickel’s 21.21 mm diameter / 5 g weight. Water comparisons exclude the container’s weight. Capacity comparisons describe volume, not exterior size or how food fits. Reference pictures identify the object; use the labeled ratio for the comparison.
05 / PRICE HISTORY
The price over time.
AC Infinity MULTIFAN S2 · USB centrifugal blower · Amazon US
The chart legend identifies Amazon and new-offer prices when available. New offers can include marketplace sellers. Coupons, shipping and size/color selections can change the final price. Blank periods are missing observations, not a zero price.
06 / RELATED FINDS
A few useful extras.
For the way you plan to use it.
Power it from an outlet
AC Infinity Turbo Fan Adapter
The Turbo Fan Adapter explicitly lists the S2 as compatible. It is the matched wall-power option.
Keep the cable clear
Gardner Bender Beaded Cable Ties
Reusable beaded cable ties can gather slack away from the blower intake.