Before calling a professional repair contractor, begin by addressing the problem yourself through a few basic steps to identify more common malfunctions.
First, make certain that your current air conditioner filter is clean. If cool air is not blowing as freely as usual and ice has accumulated on or about an outdoor or indoor air conditioning unit, shut off both unit and fan for 6 to 8 hours to melt the ice. Keep in mind that the visible buildup is just the "tip of the iceberg" that has built up inside ducts, coils, and/or evaporator. Thus, it takes several hours to give all ice inside the unit to thaw completely.
Prior to turning the power back on, verify that all registers are fully open, the filter is clean, and that surrounding areas near return and supply registers are free of debris.
Call a qualified air conditioner repair service if the system re-freezes. This could mean a freon deficiency. If the repair tech puts more freon into your system but cannot identify a leak, consider buying a "freon leak repair kit" online that is easy to use yourself.
Keeping all coils inside your air conditioner clean is an essential DIY maintenance task. Fortunately, it is also very easy to do. Simply spray all coils with a good coil cleaner. Then, allow the liquid to saturate all surfaces completely.
Next, flush them with clear water to remove all trapped grass and other foreign matter. You should then clear all vegetation in a 12-inch radius of an outdoor unit. Numerous air conditioner maintenance kits are available for sale online. These products come with coil cleansers, brushes, a coating solution, and a fine-toothed comb. Use the kit to clean outdoor air conditioner condenser coils at least twice per season. Indoor air conditioner coils might not require as frequent cleansing if you stay on top of replacement and use only high-quality air filters.
Maintaining your coils in a clean condition also facilitates reduced energy costs. Always make certain to turn the air conditioning unit off by using the main breaker prior to performing any DIY maintenance.
Also, never work without wearing gloves and safety goggles whenever you use a coil cleaning solution.
Clogged evaporators in outdoor units or dirty indoor coils in indoor air conditioners can cause system freezes. In addition, dirty outdoor air conditioning unit coils and indoor condensers cause inefficient performance during very warm weather.
Another symptom of a dirty outdoor unit is when the surface of the small copper line that exits the unit is too hot to touch while the air conditioner is operating.
Remember that merely because you cannot see dirt, dust, or debris on the outer surface of an outdoor air conditioner coil does not mean it is clean.
The better coil cleaners are capable of deep penetration into a coil to dislodge and scour away interior dirt and debris. Thus, keep such a product on hand at all times to prevent the needless early death of your air conditioner compressor.