First, the temperature will be uneven throughout any given building. In order to ensure that the outskirts of a large building are adequately cooled, the interior may end up frigid. This effect is more pronounced with larger buildings. Please complain to your nearest HVAC contractor, not to us poor Texans.
Second, people who are just coming in from 115 F outdoor temperatures actually tend to want it to be nice and cold inside. Believe me.
Third, the outdoor temperature varies over the course of a day. A thermostat setting that resulting in an acceptable actual indoor temperature at noon might be causing very cold indoor temperatures at 6 PM, even though nobody touched the thermostat.
Fourth, colder air is drier, which causes sweat to evaporate faster. So there’s a sweat-evaporating benefit along with the rapid cooling benefit, which is very beneficial and widely appreciated when every single person entering a building is drenched in sweat.
The best way to learn these lessons is to simply live in Texas and observe your own behavior vis-a-vis air conditioning preferences.
Fourth, colder air is drier, which causes sweat to evaporate faster.
No, it does not work that way. Artificially cooling air without taking water out of it decreases its equilibrium vapor pressure while keeping its absolute humidity constant, thereby increasing its relative humidity and making it worse at drying things. (Conversely, artificially heating air without adding water to it makes it better at drying things.)
As Lumifer said, air conditioners extract water from the air. Then the air warms up again slightly as it percolates through the building. The net effect is enhanced drying.
Not sure what “powerful” means in this context. I have a degree in chemical engineering so I’m moderately confident that I understand compression and saturation pressure. Saturation pressure of water in air declines with temperature. Making the air colder reduces the humidity of the air, and this is true all the way down to the freezing point of water. In a large building, you will have a pump outlet temperature much lower than the thermostat setpoint. For example, the coils themselves may be operating at 25-45 F, even though the air in in the building at large may be 75 F. The consequence of this is that the percent saturation (“humidity”) of the air will be significantly lower than the outdoor humidity. The net effect will be perceptible drying.
First, the temperature will be uneven throughout any given building. In order to ensure that the outskirts of a large building are adequately cooled, the interior may end up frigid. This effect is more pronounced with larger buildings. Please complain to your nearest HVAC contractor, not to us poor Texans.
Second, people who are just coming in from 115 F outdoor temperatures actually tend to want it to be nice and cold inside. Believe me.
Third, the outdoor temperature varies over the course of a day. A thermostat setting that resulting in an acceptable actual indoor temperature at noon might be causing very cold indoor temperatures at 6 PM, even though nobody touched the thermostat.
Fourth, colder air is drier, which causes sweat to evaporate faster. So there’s a sweat-evaporating benefit along with the rapid cooling benefit, which is very beneficial and widely appreciated when every single person entering a building is drenched in sweat.
The best way to learn these lessons is to simply live in Texas and observe your own behavior vis-a-vis air conditioning preferences.
No, it does not work that way. Artificially cooling air without taking water out of it decreases its equilibrium vapor pressure while keeping its absolute humidity constant, thereby increasing its relative humidity and making it worse at drying things. (Conversely, artificially heating air without adding water to it makes it better at drying things.)
As Lumifer said, air conditioners extract water from the air. Then the air warms up again slightly as it percolates through the building. The net effect is enhanced drying.
The more powerful the AC, the less it dehumidifies. How about you talk to an HVAC contractor.
Not sure what “powerful” means in this context. I have a degree in chemical engineering so I’m moderately confident that I understand compression and saturation pressure. Saturation pressure of water in air declines with temperature. Making the air colder reduces the humidity of the air, and this is true all the way down to the freezing point of water. In a large building, you will have a pump outlet temperature much lower than the thermostat setpoint. For example, the coils themselves may be operating at 25-45 F, even though the air in in the building at large may be 75 F. The consequence of this is that the percent saturation (“humidity”) of the air will be significantly lower than the outdoor humidity. The net effect will be perceptible drying.
Yeah, but that’s not what air conditioners do. They do take water out of the air via condensation on the coils.