mmarshall

As temperatures drop, some car-owners forget that many Owners' Manuals (and technicians) recommend running the air-conditioning compressor for at least 5 to 10 minutes a week to keep the compressor-seals and hardware lubed and in good working order. This is important, as not using the compressor for months on end has the same effect as not running a gas-engine...it will deteriorate and corrode from lack of use. With modern climate-control systems, one does not have to put up with an ice-cold draft from the A/C in the winter...warm air from the temperature-**** can be mixed-in with it as desired. Automatic-climate systems, of course, cut the compressor on and off as needed, and automatically cut it on and off sometimes in the defog/defrost mode to provide a source of dry air. In manual systems, sometimes the compressor still comes on automatically with the defog, so is also important, sometimes, to mix in some warm air so the windshield doesn't chill down and start accumulating condensation/moisture on the outside.....then you need the wipers.

This policy may not (?) apply, of course, to some hybrids and/or conventional vehcles with electrically-operated compressors that are not belt-driven or don't have lubricating fluids....though, of course, it wouldn't hurt the electric motor to be run a few minutes each week either.

Lil4X

Typically, the lubricant mixes with the gas to be carried through the compressor and lubricate the shaft seals. Unused, the lubricating oil drains back to the compressor or other low spot in the refrigerant loop. Mike makes a good point here that is often overlooked, particularly in northern latitudes where your car's A/C may not be used for months (except as noted). It's a good idea to cycle your home's compressor on for a few minutes, every two weeks or so, also - preferably on a day when the outside air temperature is over 55º. . . . for the same reason.

darkdream

I always run my a/c even if it is 38 degrees outside. My passengers always complain it is an ice box inside.

GiantsFan

iTrader: (9)

I always run my AC as well. I like having fresh air in the car

My0gr81

Home compressors are a different story, specially if you live in northern climes. Once the lines are frozen, running the compressor can damage it. Besides, most home compressors are of the direct drive electric motor kind, so running them shouldn't be required. The temperature here can stay well below freezing for months at a time, even during the day, so don't try that at home if you live north of the 49th.

T0ked

iTrader: (2)

Most newer cars now run the AC when the windshield defroster is activated to dehumidify the air quickly. Sometimes its not even identified that the AC is on. I can hear the compressor turn on when I switch the dial to windshield on my FJ. Its very good advice, but i think most people are doing it without even knowing! My 93 SC300 does it automatically, too. So advanced for its time...

mmarshall

With most newer cars, that is not necessary. You don't have to put up with polar-bear conditions in the winter while running the compressor. Warm air from the heater-core can be mixed in with it, coming out the vents. If your car has a rotary-type temperature-**** control for the heat, just twist it to the right when the cold air starts blowing out.....with a slide-type lever, slide it to the right.