: Why does the car AC feel cold even when it’s set to a higher temp than the ambient temperature?


I’ve noticed in colder months when the temperature is low like 8 degrees, the car AC still feels cold even though i’m technically heating the car by setting the temp higher than the ambient temp e.g. setting the car to 20 degrees but the air coming out still feels ‘cold’.

In: 0

You’re not warming the car.

In modern car climate control systems the temperature setting is a goal for the air temperature inside of the car, not the temperature of air that its blowing out.

Most systems have two settings – AC on and AC off. If you set the AC to on, it runs the air-conditioning compressor, cooling any air that is coming out of the vents.

If you set the AC to off, then the air is blown through a heat exchanger inside the engine, which heats the air up before it comes out of the vents.

If you’ve set the AC to on but your target temperature is higher than the interior temperature, most systems will just blow air through the AC compressor at the lowest possible fan speed. Some smarter systems will turn the AC compressor off, though all you’re getting at that point is outside temperature air.

If you want to actually heat your car then you need to turn the climate control on and the AC off.

It’s 8 degrees outside and your car is parked outside, so it’s 8 degrees inside the car.

You start the engine, and set the thermostat to 20. In response the system starts to heat the air up from 8 to 20.

Now you get in the car. You’re cold, because your body is 37 on the inside and about 24 feels most comfortable, because that allows your body to reject the heat that it generates.

Even after the cabin temp reaches 20, the air still cools you because it’s cold, and blowing right on you. Even air as high as 30 could feel cold, thanks to the cooling effect of it blowing right on you, because 30 is less than your internal body temp of 37