Three Ratings

• Sensible effectiveness - temperature recovery only.
• Latent effectiveness - moisture recovery only.
• Total (enthalpy) effectiveness - both combined.

Why the Test Point Matters

Effectiveness is not constant. It falls as face velocity rises and shifts with the temperature difference. A single headline number is only true at one operating point.

Reading the Curve

A credible rating shows effectiveness across several airflows. Use the point closest to your real duty, not the best-case marketing figure.

Standards

EN 308 and AHRI 1060 define how these numbers are measured so different products can be compared fairly.