re: How do some think an HVAC thermostat controls the temperature of the air blowing out?

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Sort of, the car is still producing the same cool or heat temp no matter what the setting once it has been running long enough.. Difference is that there auto systems blend in air to slow or increase the rate of change. But it's not like if you set it to 78 that it will blow out 78 degree air. It doesn't work that way

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I know how a blend door works, but wasn’t going to go into depth explaining in my post how heat from the heater core and cool air from the condensing coil is blended through a blend door/actuator to obtain a temperature.

People are familiar with the fact that they can slightly raise or lower their temp in a car and have the air blow at a slightly higher or lower temp from their vents. It wasn’t important to our conversation about home AC because that’s not how home ACs work. But for someone that doesn’t know how the systems work I could understand why they think a house might work that way.

It’s pretty easy to show people how the HVAC in the home works. All you have to do is get a cheap infrared thermometer and show them the temp at the return and then show them the temp at a vent. You can show that the air blows about the same temp no matter what they set it at. But then you may be stuck trying to explain “temperature drop” between the return and the vent (or both sides of the evaporator coil) as the house continues to cool down.

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fww - AC's do not make air "cold", they remove the heat from existing air leaving it cooler.

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Yes. That’s how it’s done. So they make the existing air going into the unit colder when it comes out of the vents. Of course, the set threshold of the thermostat does not determine the temperature of the air coming out of the vents.

This has really turned into a technical HVAC thread. Very similar to those weather threads.

Thread tldr- women think turning down the thermostat to 72 will make the air come out of the vents at 72 and turning the thermostat down to 58 will make the air come out at 58

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Very similar to those weather threads.

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I've RA'd the mods requesting this be moved this to the "The faster you drive, the better your mpg" board.

Been trying to explain this to people for years, especially in automobiles

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If it is lower than you probably have an issue

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Bruh. I pay a guy with a freaking Polar Bear on his white van. A Polar Bear.

He makes it cold, the wife is happy. I get to live another day.