[guytanatz]

In the summer we use auto and both the fan and the AC compressor kick on to pump out cold air. In the winter, does auto also turn on the compressor or is it just the fan? I'm just trying to figure out if auto has the same impact on fuel consumption in the winter as it does in the summer.

[wilbur_the_goose]

You will often want AC on in the winter, especially to keep condensation in check (defogging your windows)

[Billfitz]

Originally Posted by guytanatz

I'm just trying to figure out if auto has the same impact on fuel consumption in the winter as it does in the summer.

Since the compressor will only run when required for removing condensation, which is before the engine has warmed up enough for the heater to work, it's going to have very little effect.

[guytanatz]

Originally Posted by Billfitz

Since the compressor will only run when required for removing condensation, which is before the engine has warmed up enough for the heater to work, it's going to have very little effect.

I guess my question is if I just want to be lazy and hit auto in the winter does the compressor still kick on?

[Billfitz]

Only when it needs to.