A/C running in cold weather?

[mrqz]

Hi there guys, this could be interesting in case of most cars, but specifically in the PHEV, how does the A/C compressor operate in cold, ie. <5 deg C?

I always knew it as the compressor's operation (spin up) is restricted by the car ECU under such temps to avoid freeze damage to the compressor. But does it really work that way in our cars? Today in 0 deg C, I unintentionally switched the A/C on and it seemingly (audibly) started up and kept on working. I waited some 60 sec and switched it off. Do you think if it can work in temperatures around zero without getting frozen up, or does the ECU really disable the operation of the compressor in such circumstances (and if the latter, does it happen with immediate effect or with some tolerance?)

 

[MrPastry]

I have never given it much thought, but always use the a/c in the cold/wet winter months to prevent the cabin misting up.

 

[mrqz]

I have never given it much thought, but always use the a/c in the cold/wet winter months to prevent the cabin misting up.

I have done so as you describe in my previous cars (Saabs) but what I noticed over time is that in cold (say below 4-5 degrees C), the compressor felt as it worked the same as in warm (noise, rolling resistance) however in this case it wasn't de-misting the windshield anymore. From these occurences I always drew the conclusion like "oh yeah, so it stopped operation to avoid freezing up".

 

[generaltso]

Every car I've ever owned has used the A/C compressor when defrosting the front windshield in winter. Even in temps down to -20F, I've never had a problem.