"The Exception To The Rule"

MultiTherm 503 ®
Non-Toxic Heat Transfer Fluid for Process Heating and Cooling

MultiTherm 503 Physical Characteristics
Chemical Type Paraffinic Hydrocarbon
Appearance Bright, Clear, Colorless
Odor None
Pour Point, ASTM D97

<-76°F / <-60°C

Density @ 16°C

6.64 lb/gal

Flash Point, COC, ASTM D92

310°F / 154°C

Fire Point, COC, ASTM D92

345°F / 174°C

Atmospheric Boiling Point (10%) ASTM D1160

616°F / 324°C

Average Molecular Weight


Maximum Film Temperature

550°F / 288°C

Maximum Recommended Operating Temperature

500°F / 260°C

Pumpable, Centrifugal @ 2000 centipoise

-73°F / -58°C

Heat of Vaporization @ 500°F

106 Btu/lb
247 kJ/kg

Heat of Combustion

20,340 Btu/lb
47.3 MJ/kg

Coefficient of Thermal Expansion




MultiTherm 503® process heating and cooling in standard low pressure equipment

MultiTherm 503®
is a high quality non-toxic heat transfer fluid for use in closed loop liquid phase heating and cooling systems from 10°F to 500°F.

MultiTherm 503® has been successfully used in a variety of applications. In the Chemical Process Industry , it has been used for heating and cooling batch reactor systems. In the Plastics Industry, MultiTherm 503® has been used for hot/cold cycling of molded products and to improve the versatility of laminating lines. MultiTherm 503® provides users with a non-toxic, low pressure alternative to synthetic chemical based heating/cooling fluids. MultiTherm 503® meets the requirements for FDA regulations 21CFR178.3620(b) non-food articles in contact with food.

MultiTherm 503® provides users with a safe, durable and economical heat transfer fluid without the potential hazards posed by some conventional thermal fluids.

Promotes Plant and Personal Safety MultiTherm 503® has distinct advantages over many synthetic heat transfer fluids. It contains no components recognized as Hazardous Chemicals under OSHA Hazard Communication Standard. There are no Reportable Substances under SARA Title III (302) (304) (311) (312) (313). The fluid does not normally cause skin irritation on contact. Vapors may have a mild odor but do not normally cause respiratory irritation. All these advantages combine to provide a safe, user friendly alternative to synthetic fluids.

Lower Costs
Reduced Maintenance Costs MultiTherm 503® can help reduce system maintenance costs. It has excellent metal coating properties and lubricity, which reduce wear on moving parts and protects surfaces from corrosion. Chemically inert, it won’t attack gaskets and seals. And since MultiTherm 503® operates in low pressure equipment, there are no pressure control or purging systems to maintain. Minimize Leak Testing Fluids with high vapor pressure can require extensive leak testing prior to start-up to prevent fluid loss during operation. This can add significantly to total maintenance down time. With MultiTherm 503®, system pressure is limited to pump circulating pressure so leak testing requirements are significantly reduced.

Warranty: MultiTherm® warrants that MultiTherm 503® conforms to the data set forth in this brochure. We present this information in good faith, but because we cannot control or anticipate the many different conditions under which our information and product may be used, no other warranty, expressed or implied, is given.