RELATHERM ULT - Ultra Low-Temperature Heat Transfer Fluid | -100°C ~ 65°C

Relatherm ULT is an extended-life thermal fluid engineered for chillers and cryogenic equipment. With a usable range from −100 °C (−148 °F) up to 65 °C (150 °F) , it delivers reliable sub-zero pumpability and can serve as a dual-use fluid when a process requires both heating and cooling.
Formulated from high-purity base fluids plus advanced additives, Relatherm ULT provides exceptional oxidation resistance to minimize sludge, reduce fouling, and extend service intervals—lowering maintenance costs and downtime in demanding low-temperature applications.

PFAS-Free: Contains no Polyfluoroalkyl Substances (PFAS). Low Environmental Impact: Low Global Warming Potential (GWP = 10).
−100 °C to 65 °C Ultra-Low Temp Cooling PFAS-Free Low GWP (10)
Temperature Bandwidth: −100 °C to 65 °C (−148 °F to 150 °F) for true ultra-low temp performance.
Pumpability: Flow assurance in sub-zero conditions to protect pumps and seals.
Oxidation Control: Two-stage antioxidant package minimizes sludge and heat-surface fouling.
Safety Data Sheet (SDS) Technical Data Sheet (TDS) Certificates of Analysis (COA) End-Use Certification
Why choose Relatherm ULT?

Ultra-low temperature performance — cools processes down to −100 °C (−148 °F) with reliable pumpability.
Dual-use capability — wide operating band supports both cooling and mild heating in a single loop.
Maximum oxidation protection — robust additives reduce sludge and surface fouling for longer uptime.
Extended fluid life — engineered for longevity even in oxidation-prone systems.
ESG-minded formulation — PFAS-free with low GWP (10) to reduce environmental impact.
Technical Specifications
Model
Relatherm ULT — Ultra-Low Temperature Heat Transfer Fluid
Minimum Use Temperature
−100 °C (−148 °F)
Maximum Use Temperature
65 °C (150 °F)
Flow Assurance
Remains pumpable within specified temperature bandwidth
Oxidation Protection
Two-stage antioxidant package; minimizes sludge and fouling
Environmental Profile
PFAS-Free; Low GWP = 10
Additive Suite
Metal deactivators, rust inhibitors, seal/gasket extenders, proprietary agents
Recommended Applications
Process chillers, cryogenic equipment, low-temp reactors, thermal loops
Service Life
Extended versus conventional ultra-low temp fluids (under proper operating conditions)
Typical Appearance
Clear, low-viscosity thermal fluid
FAQ

How cold can Relatherm ULT safely operate?

Relatherm ULT has a minimum recommended use temperature of −100 °C (−148 °F) , maintaining pumpability for reliable low-temperature circulation.
Can Relatherm ULT be used for both cooling and heating?

Yes. Thanks to its wide operating band (−100 °C to 65 °C), Relatherm ULT can function as a dual-use thermal fluid in processes that require both heating and cooling.
What protects against oxidation and sludge formation?

A sophisticated two-stage antioxidant system with metal deactivators and rust inhibitors helps reduce sludge and fouling, extending service life and uptime.
Is Relatherm ULT environmentally friendly?

Relatherm ULT is PFAS-free and has a low GWP of 10 , supporting sustainability goals without sacrificing performance.
What if Relatherm ULT isn’t a fit for my application?

We offer a comprehensive portfolio of thermal fluids and system cleaners. Speak with a Thermal Fluids Expert to find the best match for your duty cycle and temperature targets.

Specifications