Liquid cooling specialist LiquidStack has launched a single-phase cooling product, following environmental concerns over the fluids used in two-phase systems.

The as-yet-unnamed product will be available from 1 December, LiquidStack CEO Joe Capes said, announcing the system at DCD Connect Virginia. Prices and product details will be available on that date.

liquidstack image
– LiquidStack

“LiquidStack is unwavering in its ambition to support the future of AI and other high compute processing,” said Capes. “Since LiquidStack’s launch, our mission has always been to become a full-service provider of the most advanced liquid cooling solutions in the market, and our new single-phase offering is a key step toward completing our liquid cooling technology stack.”

Until this week, LiquidStack has been known for its two-phase cooling system, in which a fluid boils and recondenses. Capes has previously said this is more efficient for high-density deployments than single-phase solutions which immerse equipment in large tanks.

However, two-phase cooling systems use fluorinated solvents like 3M's Novec, which was recently withdrawn because of health concerns over the PFAS class of substances, also known as "forever chemicals."

Capes told DCD in February that LiquidStack has alternatives to Novec, which are better: "There are several fluid vendors who manufacture generic versions of 3M’s fluids and, thankfully, these options have been available for quite some time. Further, LiquidStack has been testing advanced alternative fluids independently and with our customers over the last two years with results that outperform 3M’s fluid portfolio."

LiquidStack says its new single-phase option performs better than the W32 thermal guidelines set forth by ASHRAE (the American Society of Heating, Refrigerating and Air-Conditioning Engineers), and can remove more than 2.8kW of heat per rack unit (or 110kW per rack), which is enough to run AI workloads based on GPUs.

The system uses non-hazardous fluids and Capes promises the pricing would give "assured value" and a favorable total cost of ownership.

Capes says that rival immersion systems can only remove less than 100kW of heat in a full-size tank.

The LiquidStack solution occupies the same footprint as four typical racks, so it should retrofit into existing facilities and can hold modules including 1U, 2U, 4U, 600mm, 750mm, OCP, and ORV3.