KZ14038B012U 140mm 6-Pin Cooling Fan 12V 7.2A – Whatsminer M20 / M21 Series
The KZ14038B012U is a 140×140×38mm dual ball-bearing cooling fan rated 12V / 7.2A, delivered with the 6-pin connector used on the Whatsminer M20 / M20S / M21 / M21S series. It is the high-current, high-static-pressure variant — built for the airflow load of M20-class hashboards, where fan failure quickly cascades into chip-level overheat and shutdown. The fan ships with the original Whatsminer 6-pin pinout, so the controller reads its tach signal correctly and does not throw a fan-error.
4-Pin vs 6-Pin Variants
Whatsminer used two connector revisions for the same physical 14038 fan: a 4-pin variant on M30 / M31 / M32, and a 6-pin variant on M20 / M21. The fan housing and electrical curve are identical — only the connector and pinout differ. Make sure to order the right variant for your miner: a 6-pin fan plugged into a 4-pin header (or vice versa) will not seat and will trigger an immediate fan fault.
Replacement Procedure
Power down the miner and disconnect mains. Unscrew the chassis fan grille, lift out the failed fan and unplug its 6-pin lead from the controller header. Fit the new KZ14038B012U with the airflow arrow pointing the same direction as the original (check intake vs exhaust slot). Reconnect the 6-pin lead, refit the grille, and power on. Confirm in the dashboard that the fan reaches normal RPM within 5-10 seconds and that hashboard temps stay within their target range.
Restocking 6-pin KZ14038B012U fans for an M20 / M21 fleet? Contact us at contact@lys-sz.com for case-quantity pricing. Worldwide shipping from our Shenzhen warehouse.
📦 Shipping & Customs⌄
🇺🇸🇪🇺 USA & European Union (DDP): Orders are delivered DDP. All customs duties, import taxes, and fees are included — no additional charges on delivery.
🌍 Rest of world: Orders ship from China. Depending on your country, local customs authorities may apply import duties or taxes.
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