CR Box Air Purifier - IKEA UPPÅTVIND Filters

Description
Cost-effective enclosure that utilizes the original IKEA UPPÅTVIND filter, replacing the single stock fan with two 120 mm fans for significantly higher airflow.

Tested with two Thermalright TL-C12C fans at 12 V: total measured ≈145 CFM (vs ~60-65 CFM of the original IKEA unit at similar noise).

Rear side has no fan grills – suitable for my own use (kids/pets not present).

Required parts (beyond printed enclosure)

• 1× IKEA UPPÅTVIND replacement filter (original or generic)
• 2× Thermalright TL-C12C 120 mm fans (or any 120×120×25 mm fan with similar performance)
• 1× DC5521 female to 4-pin PWM fan splitter/adapter https://www.aliexpress.com/item/1005004616666088.html
• 1× USB-A trigger cable 5 V → 12 V step-up (3 A capable) https://www.aliexpress.com/item/1005004974676688.html
• 1× USB-A 5 V power supply ≥ 15 W (recommended 5 V @ 3 A; measured fan draw 4.8 W total at 12 V)
• Optional: variable 12 V bench supply or smart plug for on/off scheduling

Assembly notes

1. Fan airflow direction: install both fans so the label side (with technical data) faces the rear of the enclosure (air is pulled through the filter from the front).
2. Fans can be daisy-chained using their native 4-pin connectors or wired directly to the DC5521→4-pin adapter.
3. DC5521 barrel jack is a tight fit, but it could come loose when inserting the power supply. Glue can be used to secure it permanently if desired.
4. Plug the USB cable into any suitable 5 V source.
5. Optional:  I use a smart plug to control the unit.