A thermometer only measures sensible heat. Humid air carries hidden latent heat too — moisture that must be condensed out — which is why the same temperature drop removes far more total energy from humid air.
Psychrometrics studies the properties of moist air — temperature, humidity, and the energy (enthalpy) associated with both. A thermometer only reveals sensible heat (the temperature-related component), but humid air also carries latent heat, the energy bound up in water vapor that must be released (condensed) to actually remove that moisture — and cooling systems have to remove both, not just sensible heat, to properly condition humid air.
Sensible heat is the energy associated with a measurable temperature change — the heat a thermometer would register cooling or heating air. Latent heat is the energy associated with a phase change (water vapor condensing into liquid water) at essentially constant temperature — it doesn't show up on a thermometer, but it's very real energy that a cooling coil still has to remove to actually dehumidify the air, not just cool it.
As shown above, at higher relative humidity, a much larger fraction of the total cooling load is latent (moisture removal) rather than sensible (temperature drop) — this is exactly why the same temperature-based comfort target requires a dramatically larger total cooling capacity in a humid climate than a dry one, even though the thermometer alone doesn't show the difference.
HVAC equipment must be sized against total cooling load (sensible plus latent), not sensible load alone — undersizing latent capacity in a humid climate leads to a space that reaches the target temperature but stays uncomfortably humid (and potentially prone to mold/moisture problems), since the equipment satisfied the thermostat's sensible-heat-driven call before adequately dehumidifying the air. This is why psychrometric analysis, not simple temperature-only load calculation, is standard practice for proper HVAC sizing.
A thermometer measures temperature, which reflects sensible heat content — latent heat is energy associated with a phase change (water vapor condensing to liquid) that occurs at essentially constant temperature, so it doesn't register as a temperature change even though real energy is being released or absorbed.
In practice, no — any cooling coil operating below the air's dew point temperature will condense some moisture out of the air as a natural side effect of cooling it, which is exactly why air conditioners produce condensate drainage. The relative split between sensible and latent cooling depends on coil temperature and airflow design, but some latent removal is essentially unavoidable when cooling humid air below its dew point.
Because a thermostat only responds to sensible (temperature) conditions — if the cooling equipment has enough sensible capacity to hit the setpoint but insufficient latent (dehumidification) capacity for the actual humidity load, the space can reach its target temperature while remaining uncomfortably humid, since temperature and humidity are genuinely separate quantities that both need to be adequately addressed.
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