Moving into a New Home: How to Choose an Air Purifier for the Bedroom?

Budget-Friendly Air Purifiers for Small Spaces

For bedrooms, considering small air purifiers in the thousand-yuan range is a viable option. Despite their compact size, these purifiers follow the same purification logic as larger models:

They filter and adsorb pollutants like dust, odors, formaldehyde, bacteria, and viruses from the air using different filter materials, eventually releasing clean air.

Apart from a smaller maximum coverage area, there’s no significant difference in filtration performance. Hence, for small spaces, these affordable purifiers can effectively meet expectations.

However, in this price range, there’s a proliferation of lesser-known and counterfeit brands. Careless purchasing could lead to ineffective or even harmful products.

Kit hopes this article will educate readers about selecting air purifiers for small spaces, what to focus on, and share insights from personal testing of four thousand-yuan air purifiers based on brand, sales, and reputation.

Key Points to Consider When Choosing a Budget Air Purifier:

Despite being budget-friendly, these purifiers might lack the advanced features of more expensive models. Follow Kit’s guide to make an informed choice:

1. Pay Attention to Dual CADR Ratings:

The most critical parameter to consider is the dual CADR rating: Particle CADR and Formaldehyde CADR. The CADR indicates the volume of air processed per unit time; a higher CADR means better purification. Different CADR ratings exist for particles (like PM2.5) and gases (like formaldehyde).

The CADR also gives an estimate of the purifier’s coverage area: 0.07CADR~0.12CADR=Applicable Area. The coefficient varies based on indoor pollution level, with lower values for more polluted areas, such as newly renovated spaces. For example, a 20㎡ space would require a purifier with a CADR of 166-285m³/h.

2. Filter Configuration:

Good filtration relies heavily on filter types. Basic filters include: Pre-filters, HEPA filters, and Activated Carbon filters.

These filters, when of good quality, can handle over 95% of air pollutants like dust, allergens, and renovation pollutants like formaldehyde and TVOCs.

Some brands add functional filters for enhanced performance. Kit believes this is a bonus feature for budget purifiers:

⭐️ Bacterial and Viral Filtration:

Post-pandemic, the demand for bacteria and virus filtration has increased. Traditional purifiers use HEPA filters to trap these microorganisms. The most common HEPA grades are H11, H12, and H13, each with varying capture efficiencies.

However, without additional antimicrobial materials, these filters can become breeding grounds for microbes over time. Some brands add filters with antimicrobial properties to prevent this, making them a cost-effective solution for budget purifiers.

3. User Experience:

Aside from purification, user experience is vital. Consider:

Smaller Size:

For small spaces like offices, bedrooms, or rental properties, a compact purifier is preferable. Some models are as small as an A4 sheet.

Quieter Operation:

Low noise levels are crucial for small, quiet spaces like bedrooms or offices. A noise level below 35dB is almost inaudible, with below 30dB being ideal.

Smart Features:

Purifiers with networking capabilities and app support offer convenience. For example, Xiaomi and Huawei HarmonyOS systems can integrate with smart home systems for automated functions.

Comparison of Four Budget Air Purifiers

⭐️ Specifications of Four Purifiers:

1. Huawei Choice 720 3i:

This model stands out for its filter configuration, purification performance, and compact size. It features a 6-layer filter system, including an antibacterial layer and H13 HEPA filter. Its display shows PM2.5 levels and has a small footprint, quieter than an A4 paper.

Experience: Kit tested the 3i’s performance against heavy smoke. In 6 minutes, PM2.5 levels dropped below 30 units, and smoke odor was almost undetectable.

2. Xiaomi Air Purifier 4:

Ideal for Xiaomi ecosystem fans, it has high particle CADR and antibacterial, antiviral filters but lacks the silica layer for formaldehyde capture. It integrates well with Xiaomi’s smart home products.

Experience: Similar to the 720 3i in purification and noise, but larger and with a higher maintenance cost.

3. Philips AC0917/00:

A well-rounded purifier from a reputable brand. It uses a combination of pre-filter, HEPA, and activated carbon, with a compact size and low noise.

Experience: Solid basic performance, though not exceptional.

4. Panasonic 63C8PX:

Unique for its nanoe technology, excellent for odor filtration. It has the highest formaldehyde CADR among the four and a distinctive approach to air purification.

Experience: Excellent at filtering smoke and odors, though with a simpler display.


Each purifier has its strengths. High CADR, effective bacterial/viral filtration, and user-friendly features like low noise and compact size make a product stand out.

Kit’s Recommendations:

1. Huawei Choice 720 3i: A well-equipped budget purifier suitable for various small spaces.

2. Panasonic 63P8CX: Great for odor-sensitive users and small spaces, with exceptional formaldehyde CADR and nanoe technology.

Overall, even budget purifiers can provide excellent air quality improvement in small spaces.

Choosing an Air Purifier for Your Bedroom

When it comes to selecting an air purifier for your bedroom, there are several factors to consider. Since it’s for a new house, you’ll likely have a need for formaldehyde removal. Therefore, it’s essential to choose a filter that can break down formaldehyde. Additionally, for a bedroom, you should opt for a low-noise option, and it should be compact for easy mobility.

Here, I’ll briefly discuss the differences in air purifiers, and you can select a specific model based on your budget and preferences.

I. Structural Differences:

There are two main structural categories in the industry: “Tower” and “Column.” However, I’ll further divide them based on my experience testing over ten air purifiers.

1. Barrel-shaped Filter Tower Air Purifiers:

These purifiers have barrel-shaped filters, and air enters from all sides and is purified before being blown out from the top. Many basic models on the market use this structure. Examples include Xiaomi disinfection machine and Honeywell H-max. These use a barrel-shaped filter that is hollow in the middle, and the air is filtered from the sides. Similar structures can be found in various Xiaomi entry-level purifiers and Dyson BP04 and PH04.

The barrel-shaped filter tower air purifiers generally have lower filter resistance, making it cost-effective to achieve high airflow.

2. Traditional Stacked Filter Tower Air Purifiers:

Another type is the traditional stacked filter tower air purifiers, where the airflow and filters are in the same direction. This design allows for higher purification efficiency, but it also increases air resistance, potentially requiring more powerful fans. Therefore, these tower purifiers tend to be larger in size. Examples include 352 X88c and IQairhp250, but there are differences between them. IQair’s filter design involves compressing layers tightly and has thicker sealing foam, which enhances airtightness but makes filter replacement less convenient. On the other hand, 352’s filter is pushed in like a drawer, making it more convenient for filter replacement, suitable for daily home use. Similar structures can be found in Huawei Smart, Xiaomi Ultra, and others.

3. Upright Air Purifiers:

Upright air purifiers can be categorized into two types. One allows air to enter from the sides and exit from the top, offering higher efficiency but potentially causing dust accumulation on the top over time. The other type has dual fans with air entering from the front and back and exiting from the sides, providing a larger purification area. Examples include IAM-M8, Shuleishi A02, Teralon H95, and Shuleishi B01.

In summary, for offices or rental spaces, consider cost-effective barrel-shaped structures and replace filters regularly. For home use, opt for upright structures that balance airflow and efficiency for safety and peace of mind. In heavily polluted areas, tower structures are recommended, but compare fan noise levels and filter quality.

II. Filter Composition and Lifespan:

Pay attention to the filter composition. Activated carbon can only reduce formaldehyde temporarily. Filters like zeolite can decompose formaldehyde effectively over the long term.

Apart from formaldehyde and particle filtration, some people require odor removal and sterilization. For odor removal, test results show that certain air purifiers can effectively reduce ammonia and hydrogen sulfide levels. As for sterilization, options include positive and negative ions and UVC ultraviolet light. All models except IQAIR have UV-C light. Multiple certifications like “消” (Removal) certification, medical-grade certification, baby-friendly certification, and allergen certification indicate the manufacturer’s commitment to standards and provide peace of mind.

III. Convenience of Use:

Lastly, consider ease of use. I have tested the maximum and minimum noise levels and maximum and minimum fan speeds of eight products. In sleep mode, prioritizing low noise may compromise air purification effectiveness due to reduced fan speed. Brands that focus solely on low sleep mode noise may not effectively purify the air. When it comes to volume, display, and controls, these factors are essential for long-term use. However, they may not be a top priority, as everyday activities can affect VOC levels.


Choosing a reliable air purifier involves considering CADR and CCM values, as well as understanding the specific airflow structure and filter formula advantages and disadvantages. Modern air purifiers offer a wide range of functions to meet various needs. I’ve included a table with six air purifiers for your reference. Feel free to use it, or let me know your requirements and budget in the comments, and I can recommend a suitable product for you!