With three filters, five high-powered fans, and clever airflow design, this self-built unit is giving commercial air purifiers a run for their money.
In a post on r/AirPurifiers titled “I finished Version 4 of my DIY air purifier”, the builder reveals a fascinating evolution of their home-air filtration project. What started as a simple idea — combine a fan with a HEPA filter — has grown into a serious air-cleaning machine: version 3 apparently had 3 filters and 5 fans.
What Makes It Interesting
- Multi-fan, Multi-filter construction
By using multiple fans (ARCTIC P14 Pro PST PWM 140 mm units, according to the post) and stacking filters in a clever way, the builder tackles two key constraints: airflow and filtration surface area. More fans equal more volume of air processed; more filter surface means lower resistance, so airflow isn’t throttled. - DIY ingenuity meets real engineering
The commenter on Reddit pointed out: “DIY air purifiers are great … you can install different speed controls and other things like silencers.”
This shows that the DIY build isn’t just “stick a fan and a filter together” — the builder is tuning noise, airflow, components. That elevates it from a weekend hack to something much more functional. - Cost-effectiveness & accessibility
While commercial air purifiers (especially premium ones) can cost tens of thousands of rupees (or dollars), DIY versions like this leverage off-the-shelf fans and filters. The DIY route opens up the possibility of decent indoor air quality on a tighter budget. - Visible results + community endorsement
The Reddit thread includes user replies like: “My man … I printed a bracket to fit a Noctua 5 V fan … It works extremely well.”
Real users reporting success adds credibility to the project.
What It Does & Why It Matters
Indoor air quality (IAQ) is increasingly critical — in many cities, pollution, cooking smoke, allergens, and dust contribute to stale or unhealthy air indoors. A large portion of research into DIY air cleaners (for example using the 5-filter “Corsi–Rosenthal Box” design) shows you can achieve equivalent clean-air delivery rates (CADR) of commercial units for a fraction of cost.
In this context, the Reddit builder’s version 4 is compelling because:
- It scales up beyond a simple box fan + filter.
- It uses higher quality components (140 mm fans, multiple filters) which means better airflow rates & potentially lower noise.
- The design likely handles larger room sizes or heavier pollutant loads (dust, smoke, pet dander) compared to basic DIY builds.
For someone living in a place with heavy indoor/outdoor pollution, or even just wanting cleaner home air (especially if they have a toddler, pets, or allergies) this kind of build offers a practical alternative.
Key Specifications (as revealed)
- Fans: ARCTIC P14 Pro PST PWM 140 mm (5 of them)
- Filters: Three filters in the latest version
- The builder claims it’s their “third version with 3 filters and 5 fans” (so Version 4 presumably refines that further)
While the post doesn’t list CADR values or exact room sizes, the component choice suggests serious performance. With five fans pushing air through multiple large filters, the unit would have strong throughput and likely lower static pressure (if configured well), which is important for efficacy.
Pros & Things to Note
👍 Pros
- High customisability: You can tailor fan speed, noise vs performance, filter types.
- Cost-effective compared to high-end commercial purifiers.
- Potentially high performance if designed correctly (multiple fans + filters).
- Fun project for a tech/hobbyist enthusiast — especially given your interest in hardware and DIY.
⚠️ Things to watch
- Noise: More fans = more noise unless you use quiet blades, PWM control, and dampening.
- Filter quality & type: HEPA vs MERV vs carbon matters depending on what you’re filtering (PM2.5, VOCs, odours).
- Maintenance: DIY builds still need filter replacements & general upkeep.
- Safety & certification: Commercial units often have safety certifications; DIY units may lack these. Also ensure electrical wiring is safe.
- Room size & throughput match: Make sure the build is appropriate for your room’s volume and pollutant load.
Why This Build Stands Out
What really makes this DIY build compelling is the versioning (4th iteration) and the component upgrade path. It shows someone iterating, improving, learning. That kind of craftsmanship resonates for tech-savvy readers (which matches your audience with hardware reviews, how-to articles, DIY projects). It’s not just “here’s a cheap purifier” — it’s “here’s how someone built a serious one, step by step, and refined it”.
Given your interest in hardware, PC components, and how performance matters (e.g., GPU memory latency, gaming PC vs console), you can approach this article like a hardware build review: parts list, airflow vs resistance, noise vs throughput, cost vs benefit. That angle will resonate with your audience.
Final Thoughts
If you’re looking for interesting discover-friendly content: this DIY air purifier build ticks all the boxes. It has a strong visual appeal (fans + box + filters), a clear problem to solve (poor indoor air), a clever solution (DIY + multiple fans/filters), and a “build story” element (Version 4, iteration).
