If the chilled water supply to a building is 55F, what should be your concern if it’s used for human comfort?

The correct answer is that concern arises because a chilled water supply temperature of 55°F (approximately 13°C) is generally considered too cold for human comfort in most indoor environments. Human comfort typically dictates that temperatures in living and working spaces should be maintained between 68°F and 78°F (about 20°C to 26°C).

When chilled water is used in air conditioning systems, it is circulated to cool indoor air, but if the water temperature is too low, it can lead to discomfort due to excessive cooling. Consequently, at 55°F, occupants may feel cold, leading to potential health issues like hypothermia, particularly in high humidity environments where the cold temperature can contribute to rapid body heat loss.

Maintaining comfort in environments where people spend extended periods is crucial, and water temperatures significantly below the threshold for comfort can disrupt this balance, thus raising concerns for human occupancy.