Interactive · approach-temperature model, anchored to published data

Derating simulator — capacity vs room temperature

A liquid-to-air CDU's capacity falls as room temperature rises — it scales with the approach temperature. Pick a product (or custom), then drag the operating point along the curve.

Model: Q = Q_rated × (T_coolant − T_room) / (T_coolant − T_{rated room}), floored below a 5 °C minimum approach and capped at rating. Default anchors to the published Vertiv XDU070 point (86.5 kW @ 45 °C coolant, 25 °C air). First-order illustration — real units have fan-speed compensation; demand the vendor's measured curve (RFQ item 12).

Try this

• Keep the XDU070 defaults, drag 25 °C → 35 °C — capacity roughly halves. That's the tropics.
• Custom mode, coolant 45 → 50 °C — capacity recovers. This is why warmer W-classes matter.
• Drag past coolant − 5 °C — the curve hits zero: physics, not a product flaw.