If last year’s record temperatures were any indication — 2012 ranks as one of the hottest years on record — you can plan to once again crank up your home’s air conditioner this summer.

Before doing so, though, it’s best to have your air conditioner inspected and serviced by a qualified heating and cooling company, or you could be sweating out the hottest months of the year.

A preventative maintenance inspection of an air conditioner typically includes a cleaning of the indoor and outdoor condenser coils, lubricating parts, adjusting airflow, calibrating thermostats and inspecting ductwork.

"As the system runs it accumulates dust and dirt in the condensing coils," said Brian Huft of Huft Heating & Air Conditioning Inc. in Elk Grove, Calif. "Just by removing that dust and dirt out of the coil, helps the system do as much work as it possibly can. Basically, as it gets dirt on it, it’s insulating that coil, so it can’t remove as much heat as it can if it were clean."

Many heating and cooling companies offer discounted preventative maintenance plans, in which they’ll come out and inspect the heating and cooling equipment twice a year; once in the spring and again in the fall. Often, customers who sign up for these plans receive discounts on additional services or products; as well as preferred scheduling over customers without a preventative maintenance plan. A typical maintenance service should cost somewhere between $70 and $140, depending on factors like the type of equipment being serviced.

By scheduling routine service, you can also prevent potential problems from becoming bigger, more expensive issues.

"Catching these things early is really a must," said Rob McClintock of McClintock Heating, Cooling & Electrical Inc. in Matthews, N.C. "The more consistent, periodic maintenance a system has, the fewer problems it will have and the much higher efficiency the system has. To keep that peak level of efficiency that they were originally installed at, cleaning them, calibrating them and lubricating them is a must, or you’re going to have substantial degradation in the life of the system."

A common repair issue heating and cooling technicians run into are units that leak refrigerant. R-22 refrigerant, which has been used in air conditioners since the 1970s and is commonly known as Freon, is no longer being manufactured as part of a government phase out. Newly manufactured air conditioners now use R-410A refrigerant, which is not compatible with units that use R-22. Because of this, homeowners with older units that use R-22 and who experience a leak are paying significantly more for a pound of refrigerant than they were just a few years ago. Prices are ranging drastically depending on how much companies paid for their supply, but are running as much as $200 per pound of refrigerant, including the cost of the labor.

Though customers in the past simply paid to have the refrigerant topped off, they’re now reconsidering their options, McClintock said. To start, if refrigerant needs added, that means there is a leak and the leak should be repaired. More homeowners are also looking at replacement options. There are incentives to upgrading to more efficient units, including a $300 federal tax credit for qualifying units installed this year. Many local utility providers also offer credits and rebates for upgrading to a more efficient system.

"The mindset is changing now to where the homeowners are strongly considering whether to top off and look for a leak or just go ahead and consider replacement," McClintock said. "This has happened more this year than any year I remember."

Another regular issue that Huft said he sees is just homeowners neglecting routine maintenance, like changing their system’s air filters per the manufacturer’s recommendation.

"It’s very, very important to (change) those filters," Huft said. "The system won’t cool properly and it definitely won’t work as efficiently. By keeping the system clean, the filters clean and the outdoor coils clean, the system is able to do as much work as you need it to."