Antminer S21 Hydro Miner Water Cooling Heatsink Kit

Antminer S21 Hydro Miner Water Cooling Heatsink Plate – Upgrade Miner Efficiency

The Antminer S21 Hydro Water Cooling Heatsink Plate is the cold plate that bonds directly to the BM1370 ASIC chips on an S21 Hydro hashboard and transfers heat into the coolant loop. It replaces the original S21 Hydro plate when the OEM unit develops a leak, the gasket fails, the threaded fittings strip, or the bonded interface separates from the chips after a thermal event. With a fresh, properly seated cooling plate the miner returns to its rated 335 TH/s hashrate at the expected coolant return temperature, instead of throttling or shutting down on chip-overtemp errors.

Why the Cooling Plate Matters

The S21 Hydro design relies on the cooling plate to keep BM1370 junction temperatures inside Bitmain's spec window across the whole hashboard. Even a small degradation of the thermal interface — a hairline crack, dried-out paste, partial delamination — raises the temperature gradient between chip and coolant by a few degrees, which trips the miner's thermal-protection logic and either underclocks the board or shuts it down. Operators running S21 Hydro fleets see this most often after a coolant-leak repair (the plate was disturbed) or after a long run without a coolant flush.

Installation Notes

Power off the miner, isolate from mains, and drain or isolate the coolant loop on the affected hashboard. Remove the old cooling plate by undoing the threaded fittings and the chip-side fasteners — collect any residual coolant. Clean both the chip array and the new plate's mating surface with isopropyl alcohol, apply a thin even layer of high-conductivity thermal compound, and reseat the new plate using fresh gaskets. Torque the fittings to spec, refill / pressure-test the loop for leaks before powering up the miner, and verify hashboard temperatures sit in the OEM range under full load.

Antminer S21 Hydro Cooling Plate Specifications

Related Hydro Cooling Parts

• Antminer S21 / T21 Water Cooling Plate
• Lian Li 12KW Water Cooling Kit – Hydro ASIC
• DOWSIL TC-3080 8W/mK Blue Thermal Gel (1kg)
• Antminer Hydro PSU Cable – APW11 / S21 Hydro

Refurbishing S21 Hydro hashboards in volume? Contact us at contact@lys-sz.com for fleet-quantity pricing. Worldwide shipping from our Shenzhen warehouse.