Two Forms of Energy in Air

Air carries energy as dry-bulb heat (sensible) and as water vapour (latent). A sensible exchanger moves only temperature; an enthalpy exchanger moves both. The choice changes the whole system design.

Deep Selection Logic

• Dry or cold climate - sensible recovery is usually enough; moisture is not the bottleneck
• Hot, humid climate - latent load dominates; choose enthalpy recovery
• Mixed climate - check the cooling-coil load with and without moisture recovery

How to Quantify

Compute the latent load as the mass of condensate the coil must remove. If that load is large, enthalpy recovery (rotary wheel or membrane plate) typically halves dehumidification demand and shortens payback.

Decision Rule

If the humidity-ratio difference between streams is small, a sensible plate core is the cost-effective choice. If it is large and the cooling coil is oversized, move to enthalpy recovery.