What Is a Muffin Fan?

A muffin fan is a very versatile fan with a funny name.

What is a muffin fan?

A muffin fan is a small axial fan, usually in a square frame, that moves air through equipment to carry heat away. Muffin fans are common in electronics enclosures. AC Infinity, one maker, lists tanning beds, LED signs, server racks, industrial machinery and arcade systems as typical uses.

This article covers where the name comes from, the main types and sizes, how long muffin fans last, what they cost and how to use one safely.

Why Is It Called a Muffin Fan?

When most people hear the term “muffin fan,” they immediately want to know where the fan got its name.

The name started as a brand. U.S. Patent and Trademark Office records show that Muffin was a trademark for electric motor-driven fans, registered in 1958 by Rotron Manufacturing Company, Inc.

The records show the mark was first used in January 1958 and registered that December. The registration was cancelled in October 2021.

Over time, Rotron’s brand name became synonymous with the product.

This happens in many industries. The term “Q-tips” is a brand name for cotton swabs. The same is true for Xerox, Jet Skis, Kleenex, Jacuzzis, and Bubble Wrap.

Types of Muffin Fans

There are many types of muffin fans used for various personal, business, and industrial purposes.

To really understand muffin fans, you need to know as many types as possible.

Common muffin fan types:

• Muffin fan for computers
• Muffin fan with thermometer
• High-temperature muffin fan
• Muffin fan with filter
• Solar muffin fan
• USB muffin fan
• Waterproof muffin fan
• Round muffin fan
• Muffin fan for RV fridge

What Is a Muffin Fan for Computers?

A muffin fan for computers helps regulate your computer’s internal temperature.

Computers generate a lot of heat when they are turned on. This heat can damage the computer’s internal components and reduce its lifespan.

A fan does not reduce the heat a computer produces. It draws cooler air into the case, pushes warm air out and moves air across heat sinks so the parts stay within a safe temperature.

Muffin fans for computers are related to PC fans, computer fans, or computer case fans.

Check the voltage before buying. Many fans sold as muffin fan kits, such as the AC Infinity AXIAL 1238, run on 100 to 120 V AC from a wall outlet. They are not the low-voltage DC fans that plug into a PC motherboard, and the two are not interchangeable.

What Is a Muffin Fan With a Thermometer?

Some muffin fans are paired with a temperature sensor so that fan speed follows temperature.

Comair Rotron describes fans of this kind: when the temperature in or around the system rises, the fan speeds up in proportion. The sensor reads air temperature near the fan. It is not a substitute for a dedicated thermometer.

What Is a High-Temperature Muffin Fan?

Every fan has a rated operating temperature range, and a high-temperature model is one rated for hotter air. For comparison, AC Infinity lists 32 to 140°F for its standard AXIAL 1238. Check the rating on the datasheet before using a fan near a heat source.

What Is a Muffin Fan With a Filter?

A filter over the intake side of a fan keeps dust out of the equipment being cooled.

A filter needs regular cleaning. Comair Rotron notes that as a filter clogs, airflow is impeded and the temperature inside the equipment starts to rise.

A filter is worth considering wherever the air is dusty.

What Is a Solar Muffin Fan?

A solar muffin fan is powered by the sun.

In practice this is a DC fan run from a solar panel or a solar-charged battery. Comair Rotron says brushless DC fans are usually available at 12 V, 24 V and 48 V, so the power source has to match the fan’s rated voltage.

What Is a USB Muffin Fan?

A USB muffin fan plugs into a USB port on any computer.

A USB fan runs on the 5 V a USB port supplies, so it is a small, low-power fan. If a model has a pass-through plug for linking fans together, add up the current of every fan on the chain first.

A standard USB 2.0 port supplies up to 500 mA and a USB 3.0 port up to 900 mA. Keep the total draw of the fans below the limit of the port.

What Is a Waterproof Muffin Fan?

Fans for damp or wet places are sold with an IP rating, not just the word waterproof. The IP code shows how well a device is protected against dust and water.

Look for the IP rating on the datasheet and match it to the conditions the fan will face.

Do not fit an ordinary fan in the engine compartment of a gasoline-powered boat. U.S. Coast Guard rules (33 CFR 183.410) require electrical components near gasoline engines and fuel systems to be ignition protected, meaning they cannot ignite fuel vapor. A water-resistance rating does not cover that.

What Is a Round Muffin Fan?

A round muffin fan is just what it sounds like, a fan with a round shape. Most muffin fans come in a square shape.

One example is the AC Infinity AXIAL 2589, a round fan 254 mm across and 89 mm deep.

Most likely, you will need a square-shaped muffin fan for your device, but it’s always a good idea to check the manufacturer’s instructions or website.

What Is a Muffin Fan for an RV Refrigerator?

Many RV refrigerators are absorption units. Their cooling cycle is driven by heat from a propane burner or an electric heater.

Any fan added in the vent space behind an RV refrigerator should follow the refrigerator maker’s installation manual, because that space also holds the burner and wiring.

How Do Muffin Fans Work?

Muffin fans are devices that help cool down machines and other devices by generating airflow.

The way they work is pretty simple.

A muffin fan’s blades turn, creating a flow of air through the device to cool it down.

The most common task they accomplish is preventing machines from getting so hot they damage themselves or shut down completely.

The bottom line is that a muffin fan can be used for a lot of different things, and it’s a great tool to have in your arsenal when it comes to cooling down equipment or devices.

What Does a Muffin Fan Not Do?

It’s just as important to know what muffin fans don’t do.

A muffin fan does not heat or chill air. It only moves air so that equipment can shed its heat. How much air it moves depends mostly on size: AC Infinity lists 110 CFM for its 120 mm AXIAL 1238 and 550 CFM for its 254 mm AXIAL 2589.

Muffin fans are not silent. AC Infinity rates its AXIAL 1238 at 47 dBA and says its high speed fans can be too loud for some applications. Tupavco rates its TP1511 cabinet fans at 55 dBA.

A muffin fan is not a room fan or a heater. It is built to move air through equipment.

Who Is a Muffin Fan For?

Muffin fans are for anyone who needs to move air through an enclosure, such as a server rack or an equipment cabinet. AC Infinity describes its fans as made for DIY projects that need cooling or ventilation, and as replacement fans.

Manufacturers use muffin fans to prevent excess heat from damaging the mechanics of machines.

Homeowners can use them to keep electronic equipment such as computers and video game systems from overheating.

How Many Muffin Fans Do I Need?

The number of fans depends on how much heat the equipment gives off and how freely air can pass through it. Start with the equipment maker’s guidance and the fan’s airflow rating in CFM.

However, if you want to cool down a larger device or multiple machines at the same time, opting for two (or more) fans is best.

Dual-fan kits are common. AC Infinity sells dual versions of its 120 mm fans, and the Tupavco TP1511 is a set of two cabinet fans.

Computer users often use more than one muffin fan to protect the internal systems of their machines.

Muffin Fan Sizes

Muffin fans come in different shapes and sizes. The most common shapes for muffin fans are square and round.

These are sizes from AC Infinity’s AC muffin fan range, given as width x height x depth. The last is a round fan, given as diameter x depth:

• 80 x 80 x 25 mm
• 80 x 80 x 38 mm
• 92 x 92 x 25 mm
• 92 x 92 x 38 mm
• 120 x 120 x 38 mm
• 172 x 150 x 51 mm
• 254 x 89 mm

How Long Do Muffin Fans Last?

Fan life is rated in hours, not years. ebm-papst defines it as the number of hours after which 10% of fans would be expected to have a bearing failure. AC Infinity rates its dual ball bearing AXIAL 1238 at 67,000 hours, which is about seven and a half years of nonstop running.

Heat, dust and moisture shorten fan life.

Follow the manufacturer’s instructions for care. Unplug the fan before cleaning it, and keep it dry unless it has an IP rating for moisture.

How Much Do Muffin Fans Cost?

Price depends mostly on size. On AC Infinity’s own store in October 2026, single AC muffin fan kits from 80 mm to 120 mm were listed between $16.99 and $29.99, the 172 mm AXIAL 1751 at $39.99 and the 254 mm AXIAL 2589 at $89.99.

If you’re looking for a basic muffin fan that will serve a simple purpose, be sure to shop around and compare prices. If you’re looking for a high-powered industrial muffin fan, that will likely cost more.

But, as always, be sure to do your research and find the best deal for you.

What Else Do You Need To Use a Muffin Fan?

When you go to actually use a muffin fan, you’ll need some way to mount it.

Muffin fans normally mount with screws through the mounting holes in the frame. The AC Infinity AXIAL 1238 kit includes a mounting screw set, and the Tupavco TP1511 comes with self-tapping screws.

Be sure to read the manufacturer’s instructions carefully to see what is included in the fan’s mounting kit.

You might also need:

• Fan speed controller
• Muffin fan guard (also called a grill)
• Power cord

What comes in the box varies. The AC Infinity AXIAL 1238 kit includes a power plug cord, two fan guards and a mounting screw set. Some versions are sold without guards or a plug cord.

These are mains-voltage fans with exposed blades. Fit a guard on any side that fingers, pets or loose cables can reach. OSHA’s workplace rule requires guards on fan blades less than seven feet above the floor, with openings no larger than half an inch. If a fan has bare wire leads instead of a plug, have someone qualified wire it, and never work on it while it is connected to power.

Watch this video to see how the fan (and related parts) look right out of the box:

Examples of Muffin Fans

These are examples of muffin fans whose makers publish full specifications. They have not been tested for this article.

Final Thoughts: What Is a Muffin Fan?

When you go to purchase a muffin fan, you’ll want to know how you intend to use it and the size, shape, voltage, and power you need.

A little research upfront and some notes can really make the purchasing process (and installation process), much better.

You may also like:

• What Is a Stove Fan?
• What Is a Ceiling Fan Light Kit?
• Why Are Noctua Fans So Expensive
• What Is a Monkey Fan?

Sources

U.S. Patent and Trademark Office (MUFFIN trademark record)
AC Infinity (AXIAL 1238)
AC Infinity (AXIAL 2589)
AC Infinity (AC axial fans)
Tupavco (TP1511 cabinet fans)
Comair Rotron (clogged filters)
Comair Rotron (brushless DC fans)
ebm-papst (FAQ)
OSHA (29 CFR 1910.212)
Code of Federal Regulations (33 CFR 183.410)
University of Minnesota Digital Conservancy (numerical model of a muffin fan)
IEEE Xplore (research)

Reviewed October 2026. We corrected the origin of the name using trademark records, replaced the product picks and the noise, lifespan and price claims with makers’ published figures, removed personal claims, and added voltage, guard and boat engine safety notes, using the U.S. Patent and Trademark Office, AC Infinity, Tupavco, Comair Rotron, ebm-papst, OSHA and U.S. Coast Guard rules.