Why Your Car’s AC System Needs Repair, Even During Winter

by Rob Hopp, Cars for Keeps Owner

Most drivers don’t give a second thought about air conditioning (AC or HVAC) when the weather is cooler than about 75°f. While once considered a luxury, often an expensive add-on to a new car purchase, air conditioning is now a common factory installed item running in concert with several other systems.

Two of the most frequent questions we receive are:

1. Should I run my AC in the winter?

Many vehicles now incorporate running the air conditioning system when the windshield defroster is selected. Automatic climate control systems in the higher end vehicles use it routinely unless you select the “Economy” mode. There are a few reasons it's a good idea to run your auto's AC in the winter.

First, running the air conditioning year round will help maintain the system. It will help to keep the system well lubricated and leak proof. This is because the refrigerant actually carries the oil and sealers that lubricate the system and most importantly the compressor. It also keeps the seals and hoses moist, thus preventing them from drying out and cracking, which can lead to leaks.

Air conditioning removes moisture. If you’ve driven in heavy rain or high humidity, you needed the humidity removed from the forced air blasting your windows. This is less noticeable in colder weather, however the moisture is still a factor in clearing that fog from your view. If you have a car with a separate A/C switch, try turning it on next time (even if the temp is set on hot). It will clear your windows quicker.
2. If my AC needs repair, why shouldn't I wait until warmer weather?

Because the systems are so integrated, waiting to repair the AC system can increase the costs dramatically. Items from simple hoses, connections, desiccant chambers (driers) to the complex compressor, evaporator and condenser depend on operating in a lubricated, moisture free environment. Electrical switch or sensor failure will leave the system inoperative, but the failure of a seal or hose can cause much more serious damage. Faulty hoses will leak refrigerant, allowing water to enter the internal AC system and cause corrosion and rust.

Cars for Keeps includes testing AC function in its routine inspection process to help you avoid surprises when the weather warms up.

One more way we fix cars. For keeps!