GermGuardian AC4100 Review – Price Effective

Today, we are giving you the GermGuardian AC4100 Review to see if this air purifier still has enough gas in its tank for today or not.

When it comes to finding a budget air purifier, there is no better choice than the GermGuardian AC4100. In fact, this unit has been known as one of if not THE best under 50 dollars options on today’s market! So what does its latest review say? Does gas still power these cleaners, or have they run dry already?

GermGuardian AC4100 is a high-performing air purifier that offers great features at an affordable price. It may have some compromises, but it’s still very competitive in this market segment, and we will take care of all those considerations for you when reviewing its performance on our site!


GermGuardian AC4100



  • Color: Gray
  • Product Dimensions: 6.5″D x 7.75″W x 11″H
  • Item Weight:5.15 Pounds
  • Control Method: Touch
  • Wattage:

The GermGuardian AC4100 is a tiny and basic-looking air purifier. It doesn’t have any flashy features, and it’s made mostly of plastic. Its main goal is to be small and easy to transport, so you can take it with you wherever you go.

This air purifier is one of the most compact air purifiers in the world. It is 11 inches high and only 4.85 lbs in weight. The Blue Pure 411 with 3.4 pounds, or SilverOnyx 3-in-1, is not as light as this air purifier.

The GermGuardian AC4100 air purifier is a fantastic value for those looking for a high-quality machine without all of the bells and whistles of more expensive versions. This machine has two air intakes and one output, which helps it run more efficiently.

The control panel is missing on other GermGuardian air purifiers. You will only have one switch and one button on the front of the GermGuardian AC4100. The HEP-15 is a good desk or side table air purifier. So the button or switch on the front is acceptable. Usability

This air purifier doesn’t have any lights. That means that when you turn it on or change the fan speed, there won’t be any lights that come on. If it did have lights, some people who are sensitive to light might not like it because it would be too bright in a dark room at night. This is a problem with most other air purifiers.

Many air purifiers have control panel LEDs that turn on when the machine is in use. This can be a problem for some people because it makes it difficult to sleep in a dark room at night. The Winix 5500-2 and Coway Mighty are two of the top-rated air purifiers we tested, but their control panel LEDs cannot be turned off. The AC4100 and Levoit LV-H126 were two of the few air purifiers we tested that either don’t have control panel LEDs or that allow them to be turned off completely.

The AC4100 is quite transportable. Even with its metal shell exterior, it is physically small and reasonably light-only 5 lb. even without the internals.

The following are some of the specific characteristics that this device lacks. Such as a timer. Most other air purifiers on the market come with a timer. Many have an auto mode, sleep mode, air quality meter, etc. This unit lacks those features. This unit does not have a remote control or smart functionality.


Particle Filter

This purifier comes with a true HEPA filter, which is impressive for the price. A true HEPA filter removes particles like allergens, dust, mold, and more. This is the same particle filter type found in units that cost around $150-$900.

The AC4100 did not perform well in our performance testing because it has a low CFM. This means that it cannot process a lot of air every minute, which is important for a good air filter. This unit cannot process air quickly enough to keep up with a 150 sq. ft. room. In very small spaces (under 100 sq. ft.), it should be able to lower particle concentration to the same extent as more expensive air purifiers, although it will still take longer because of its low CFM.

Gas Filter

The AC4100 comes with a carbon filter to remove unwanted gases and smells, like VOCs and odours. This is the same type of carbon filter you find on more expensive machines, like the Coway Mighty, for example. The filter is made of a fibrous material that has been covered in carbon.

If gas filtration is important to you, we recommend a unit with a different type of carbon filter. For example, the Winix 5500-2 comes with a carbon filter that has actual carbon pellets. This type of carbon filter is much more effective at removing unwanted gases than the fibrous carbon-coated type of filter installed in the AC4100.

The AC4100 does have the same type of carbon filter as more expensive options, but the quality of the filter is much lower. During testing, fibers would actually tear-off off the filter when we removed it from the Velcro, holding it in place in the AC4100.

The carbon filter in the AC4100 has fewer and more widely-spread fibers than more expensive options. Fewer and more widely-spread fibers mean fewer fibers coated with carbon, leading to lower-quality gas filtration.


The AC4100 does not come with a separate, dedicated pre-filter. The carbon filter is responsible for both filtering gases and large particles. This issue is because gas filtration quality is reduced as the carbon filter becomes covered with large particles. The large particles cover up areas of the filter that would otherwise be able to adsorb gases. Second, the carbon filter must be replaced when it evolves full of large particles. This may happen before it becomes full of gases. And when it does become full, the filter needs to be replaced at a cost (it can’t be washed).

Some more expensive air purifiers have a separate, dedicated pre-filter. The Winix 5500-2 and Coway Mighty both come with this type of pre-filter. A pre-filter is made of a fine mesh that can be washed when it gets clogged with large particles. You can wash it over and over again for the life of the air purifier. you don’t need to replace it.

The AC4100 does not have a separate washable pre-filter. This is not uncommon in its price range. The very popular AC4825 (approx. $80) has the same setup – a single fibrous carbon filter that has to filter gases and large particles. So do the Levoit LV-H126 (approx. $60), Honeywell HPA100 (approx. $100), and many others.


The AC4100 has a UV light, but it does not work well. The bulb is very weak and is hidden behind a metal bracket at the bottom of the air purifier. It is not clear how light can contact any air.

The bottom bar is that you don’t need to buy this air purifier for its UV functionality. The good news is that you don’t need to kill germs to filter them from the air with this unit. It will do just fine, removing germs from the air in very small rooms with its HEPA filter.

Air performance

The GermGuardian AC4100 is a powerful air conditioner that can reduce the number of particles in your home to an all-time low. After only 44 minutes, this unit reduced concentration from 10k per cubic foot down below 3800, which was its lowest point during testing! The cool thing about these types of cooling systems? You don’t have any special tools or skills needed for installation, so they’re also super easy.

Most other air purifiers we tested were able to lower room particle concentration from 10,000 particles per cubic ft. down to 100 particles per cubic ft. in a short amount of time, usually 15 minutes to an hour. For instance, the Winix 5500-2 air purifier can lower the number of particles in a room from 10,000 to 100 within 15 minutes. However, the AC4100 air purifier took over 1 hour to achieve a similar result.

The AC4100 was not the only air purifier that had these results. Other “small” air purifiers (with low CFM) we tested also got the room particle concentration down to the 3,000 to 4,000 particles per cubic ft. range, but it took them a very long time to do so.

The purifier almost took the time of 44 minutes to lower the particle concentration even just (from 10,000 particles per cubic ft. to 3,800 particles per cubic ft.)

The concentration of particles was lowered for the third time, but it took an additional 1 hr. 6 minutes to get the number of particles down to 3,100 per cubic ft.

Even with this extra time, we weren’t able to get the same super low level of particle concentration (100 particles per cubic ft.) as most other air purifiers.

Air movement

The AC4100 is not effective in larger rooms because it has a capacity of only 80 CFM. This is why it is good for rooms less than 100 sq. ft and not for larger rooms.

Yes, using the device will help reduce the number of particles in a room. However, if your goal is to completely clean the air in a room, it will take more than one device. This unit will only be able to clean the air in a small room in a short amount of time. It will not be able to clean the air in a large room.

The air purifier does not completely blow clean air onto you when it is placed in front of you on a desk or directly next to your bed. Air just doesn’t work that way. As cleaned air exits the purifier, it immediately distributes throughout the room. “Dirty” air from more increased particle concentration regions in the room immediately swoops into even everything out.

The Winix 5500-2 and Coway Mighty are some of the best-rated 250 CFM units. They can be used in rooms up to 300 sq. ft. The approx. 140 CFM AC4825 can be used in rooms up to 150 sq. ft., and the Levoit LV-H126 also has very low CFM like the AC4100 so it can only be used in rooms less than 100 sq. ft.


The AC4100, like most other small air purifiers, did not do well in noise output testing. At high fan speed, it emitted 63.7 dB of noise. This is less than the 66.1 dB of a larger unit in the Coway Mighty and the 67.5 dB of the Winix 5500-2. However, both the Coway and Winix have much greater output (CFM) at these dB levels so their CFM/dB ratios are considerably sounder.

The AC4100 is not very quiet when the fan speed is set to its lowest level. It was measured at 57.4 dB, which is as loud as this air purifier gets. For comparison, the Levoit LV-H126 produces only about

The AC4100 air purifier has a noise level of 40 dB on its lowest fan speed. This is the same as the Coway and Winix air purifiers. Most of the other air purifiers we tested could be set to a low fan speed to be “whisper quiet.”

The AC4100 falls short when you compare its CFM and dB levels to those of other, more highly rated units with lower outputs. The AC4100 was measured at 63.7 dB at its highest fan speed, which is much louder than other units.

The Coway and Winix output around 100-120 CFM on their second-highest fan speed. In this setting, the Coway and Winix were each measured at 48.9 dB. This means that the AC4100 has 63.7 dB at approx. 80 CFM, while the Coway and Winix have 48.9 dB at approx 100-120 CFM. From this comparison, it should be clear which alternative is best if low noise is important to you.


The AC4100 is a well-built air purifier for its price. The unit has a metal shell and front grille, which are much more durable than the plastic shell housing of most other air purifiers on the market. Plastic shells are found even on the top-rated Coway Mighty and Winix 5500-2.

The AC4100 features a single knob for adjusting most settings.. This includes turning the unit on/off and setting the fan speed. There is a switch for UV activation, but it’s unlikely that you’ll need to use it since the UV implementation is so terrible..

The only downside to this air purifier is that you must stick small plastic feet to the bottom of the unit when you unbox it. The plastic feet are affixed to the bottom of the device with stickers and stay on the bottom of the machine. (with glue holding them in place). On the positive side of things, you don’t have to “install” them. The air purifier may be used without the plastic feet because it is so light..

Energy efficiency

The AC4100 is not very energy efficient but doesn’t use much power. This means that its less-than-stellar energy efficiency really isn’t that big of a problem. We rate energy efficiency based on how much air the unit moves per watt of electricity it uses. The higher the number – the more air per watt – the more efficient the energy usage.

The AC4100 has a power draw that ranges between 25 and 36 watts. This means that it will use between 2 and 3 Cubic Feet per Minute (CFM) of air for every watt of power it consumes.

The Levoit LV-H126 was the only other small air purifier we tested. This air purifier had much worse ratios than the top-rated larger air purifiers like the Winix 5500-2 and Coway Mighty.

These larger units are so power efficient that they use less power than the AC4100 on low fan speeds. They use less than 10 watts of power. Even at this low of an energy draw, they still have greater output (CFM) than the AC4100 on these low fan speeds.

These units have less power draw and better CFM. This makes them more energy efficient than the AC4100. The CFM/watt ratios for these units range from 10-20 on lower fan speeds and 3-5 on higher fan speeds. They also have a total power draw of 60-70 watts.

Price & Value

The GermGuardian AC4100 is a low-cost air purifier. It usually retails for around $60. The very popular GermGuardian AC4825 retails for around $80. For example, the Winix 5500-2 is available for between $150 and $200 with a minimum air volume of 250 CFM.

The filter replacements for this unit usually cost around $20. The AC4825 filter set costs around $25, and the replacement kits for the Coway and Winix cost around $40 to $60. It’s important to note that the filters for the AC4825 and Coway/Winix are much larger in surface area than other units. They also have superior efficiency to other brands, and as a result, they can remove more particles from the air at once..

The AC4100 has a lower price for filter replacements, but the filters are also smaller in terms of surface area. Coway and Winix have higher prices for filter replacements, but the filters are also larger in terms of surface area.

In General, we have to give the AC4100 only average marks for value. It’s inexpensive, but you also get a lot for your money. – not more, not less. However, if you have a smaller house, a noisier air purifier that can only be utilized in spaces less than 100 square feet is ideal.

If you only need an air purifier for a 150-square-foot room, there are several options., The AC4823 is a good example of how far you can stretch your budget; it’s about $20 less than the AC4825. However, Although you might be tempted to save money by buying a less-than-ideal air purifier, we recommend that you invest in a top-rated one, such as the Coway Mighty or Winix 5500-2.

Both the AC4100 and the 5500-2 can be used in rooms of up to 300 sq. ft. However, the AC4100 is more energy-efficient and quieter at lower fan speeds than the 5500-2. The 5500-2 offers better gas filtration and superior pre-filtration than the AC4100.

User Experience 

When I first got the Air Purifier, it was running on three and put me immediately to sleep. The noise didn’t bother me at all; in fact, after reading some reviews online about how these types of machines can help with allergies or respiratory problems (like asthma), this seemed like something worth trying out for myself! So when my mom brought home her new device from Japan – where they use electricity instead flame lamps because LEDs don’t exist yet-we set up our experiment right away…

Pros & Cons

  • Highly portable, lightweight, and tiny.
  • The air filtering technique is acceptable. The design is beautiful and compact but a little too difficult to operate. It has a solid metal shell with few buttons and Land EDs to break (a single knob controls most settings and should last a long time).
  • No light switches or any other lights that turn on. A low-cost HEPA filter
  • At full blast, it’s a little noisy.
  • Feature scarcity
  • 1-year warranty
  • The carbon filter is of poor quality in terms of durability (it tears easily) and overall performance (it contains a tiny amount of carbon)
  • The small coverage area – the unit’s 80 CFM of output is only sufficient for spaces under 100 sq. ft.


The GermGuardian AC4100 is a small and slow air purifier that is very affordable. It offers average performance in air cleaning and is similar to other small models. The only downside of this device is its high-pitched noise while operating, which may bother some people who are sensitive to noise.

Compact air purifiers are not as effective as larger models, but they can be good for occasional use or in small rooms. The GermGuardian AC4100 is a great choice for a small bedroom, but you might not like the noise it makes.

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The author is an Air purifier expert with overall knowledge of air and ionizers.