Auto cooling problems will pop up from time to time, and the more knowledge you have of your car heating and cooling system, the easier it will be for you to handle these problems. It's a mistake to never open your hood, or to assume someone else can always handle your A/C problems. It's far wiser to learn about your car, and take responsibility for its A/C system on your own.
One of the parts that might need automotive air conditioning repair from time to time is the drier. In the air conditioning process, the drier comes after the condenser, but before the evaporator. Auto cooling problems that start in the drier might require you to get a replacement for this part.
The drier acts as a filter, and helps get rid of contaminants in your air conditioning system. It also is meant to stop moisture from flowing through your A/C system, and making the system break down. Clearly, if this is malfunctioning, your A/C will be vulnerable to contaminants.
Since you need your drier to be in proper working condition, you may well replace it every few years. Specifically, if you go into the A/C system to replace any other part, the drier should be replaced as well. If you shop from the right online store, you'll find this won't be a problem, since prices are so reasonable.