Start with the loop, then specify the fluid

Trace the heat and identify the fluid boundary

A cooling diagram is the starting point for a useful fluid specification. Identify the equipment loop, its heat exchanger, and the facility system that ultimately rejects heat. A heat exchanger can transfer heat between separate fluids; it does not imply that both sides share one fluid specification.

The interactive map in this collection shows one common liquid-to-liquid arrangement. Record the actual arrangement for your project, including any equipment-specific or immersion circuits.

Build a requirements record for each circuit

Our proposed worksheet keeps the equipment requirement, the proposed material, and the supporting evidence in separate fields. This makes unresolved questions visible before a purchase order is issued.

• Which equipment model and manual revision apply?
• Who owns approval of the fluid and any substitution?
• Which materials contact the fluid, including hoses, seals, and connectors?
• What operating and storage conditions does the equipment supplier specify?
• Is this an initial fill, replenishment, or a proposed fluid change?

Keep immersion applications distinct

ASHRAE describes immersion arrangements using dielectric fluids. An aqueous cooling-fluid selection should not be carried over to an immersion bath. Begin with the immersion equipment requirements and the evidence for the specific fluid.

Revision record

1.0 · September 10, 2026 — Initial source-based edition. No original testing or equipment qualification is claimed.