When the refrigerant inside a central air conditioning unit falls below 32 degrees Fahrenheit, humidity that surrounds the coils freezes. The coils become encased in ice and the air conditioning unit fails to cool the home properly. Once you’ve thawed the coils, you have several options before calling a repair person to fix the unit. Just be sure to turn off the air conditioner first. Running the unit with the coils iced over can strain the compressor and cause it to fail. Thawing Although you may be tempted to help the thawing effort by removing chunks of ice by hand, resist that temptation. The coils and cooling fins in the evaporator portion of the central air conditioner are easily damaged. Ice clings tightly to these components, and forcefully removing it can bend fins or rupture coolant lines. Instead, turn off the air conditioner but keep the blower running. This forces warmer air across the evaporator, which hastens the thawing process. Thawing may still take several hours. Quick Fixes Restricted airflow can cause air conditioners to work harder, which results in iced coils.

Check the air filters first. If they are dirty or clogged, replace them with clean ones. Another cause of restricted airflow occurs when too many supply registers are closed. spray gun cleaning bottleCheck all the rooms in the house and ensure the registers are open. samsung air cleaner singaporeClogged and dirty cooling fins in the frame that surrounds the coils might strain the system enough to cause icing. panasonic air purifier catalogIf outside air temperatures fall below 60 degrees Fahrenheit, most central air conditioners do not work properly. Consider shutting the system off when temperatures fall below 60 degrees. Refrigerant A low refrigerant level is a common cause of iced air conditioner coils. Call a qualified service technician to check and refill refrigerant.

Air conditioning repair people understand how to work with the pressurized refrigerant system and will be able to quickly determine which type of refrigerant your system needs. Air conditioning coolants can freeze skin tissue on contact, so personal safety is another consideration. Refrigerant loss is caused by leaky systems or it may occur over time in older units. A service professional can check for and repair leaks. Contactor After thawing the coils, the air conditioner may take a long time to cool the living space again. Once the space reaches the temperature you set on the thermostat, the central air unit should automatically shut down until temperatures rise enough to warrant the air conditioner to cycle again. If the unit fails to shut off when temperatures in the living area hit the thermostat setting, the cause might be a failed electrical contactor in the outside portion of the central air unit. Like adding refrigerant, this is also a repair best left to trained air conditioning specialists.

References HVAC Parts Outlet: Troubleshooting a Frozen Evaporator CoilHorizon Services: Help! My Air Conditioner is Frozen!Reliant Air Conditioning: Air Conditioning Troubleshooting: Frozen AC PipesWeathermaster: Help! Why Is My Air Conditioner Frozen? by Mark Bower and Robert Hardy click here to return to 'heater maintenance and troubleshooting' For the most part the average homeowner IS NOT able to repair their own air conditioner unit. Many of the repairs will involve removing the freon and that requires special equipment and you must be licensed to handle the freon. But a homeowner can keep the condenser and evaporator coils clean which will help the unit run longer and more efficiently. For the purposes if this article, we are referring to a split system meaning that the condenser is located outside and the evaporator (A-coil) is located in the furnace. When cleaning the coils, use a foaming coil cleaner for the outside condenser, and a low-foaming cleaning for the inside a-coil.

For the homeowner, purchasing a coil cleaner (available here) in an aerosal can is quite convenient and simple to use. Otherwise a person could purchase coil cleaner in gallon jugs at a local hvac or plumbing supply house. In this article we will explain using both type of cleaners. Step 1 - Shut off power to condenser and check to be sure it is off. Step 2 - Mix some high-foaming coil cleaner with water (per instructions) and pour into a sprayer and saturate the coils of the condenser. Spray the coils from the outside only. Step 3 - Let the coil cleaner soak for 10-15 minutes while you remove the top part of the condensing unit with the fan attached. On some units you may have to remove the whole top. Cover with plastic bags anything electrical that may get wet. Step 4 - After 15 minutes, saturate the coils again from the outside. Step 5 - Let coil cleaner soak for 5 more minutes. Step 6 - With a garden hose inside the condenser, spray the coils so the water spurts to the outside.

Never spray the coils from the outside as the water may pack the gunk tighter into the coils rather than pushing it out. Step 7 - Repeat until your rinse water runs clear through the coils. With aerosol sprays, how you clean the condenser coil depends upon the instructions on the can. Some cans are high-pressured, which means you lift off the fan and spray from the inside out. Foaming low-pressure aerosol's should be sprayed on the outside of the coil. Keep in mind that if the protective case around the outside of the coil inhibits spraying the coil, then spray the coil from the inside. Many sprays require no rinsing, just spray and walk away. Personally, I would do the cleaning twice. First time I would spray and let it evaporate without rinsing (following the instructions on the can.) Then I'd spray a second time, and rinse a few minutes later (see above for rinsing instructions). Aerosol spray cleaners are available HERE. On the inside of your home in the furnace is the evaporator -- also known as the 'air-conditioning coil' or 'A-coil' because it's shaped normally like an 'A.' The A-coil must be kept clean as air from the blower must be able to freely flow through it during both the heating and cooling season.

To clean your A-coil, follow these instructions: Step 1 - Carefully remove the panel to expose the A-coil. Don't damage any a/c or gas lines that may be nearby. Step 2 - Vacuum the dust from the coils (below). Stubborn dirt can be loosened with a toilet brush. The flat-style toilet bowl brush works best because it fits better along the bottom. Work carefully as the fins on the A-coil will bend easily. Step 3 - Spray low-foaming A-coil cleaner on the coils (below). Do this step only if it's warm out and you can run the air conditioner for 30 minutes or more. Before spraying, put on gloves, goggles and a mask. Open all windows as the fumes may be strong. Mix the A-coil cleaner according to the instructions and pour into a garden sprayer. Spray the coils until saturated. Step 4 - Put the cover back on and turn on the a/c as soon as possible. Let the a/c run for at least 20-30 minutes as the condensation must flush the cleaner from the coil. Do not flush the A-coils with water.

If the coil cleaner isn't removed right away, it may damage the coils. It may take several cycles to totally rinse the cleaner from the coils. After the first long cycle, normal cycles are fine. A note about coil cleaners. Some cleaners are designed only for the condenser coils, some are designed for the evaporator coils, and some are designed for both. The cleaners should be non-acid. Again, use high foaming for the outside condenser, and low or non-foaming for the inside a-coil. Also, if the smell of the cleaner bothers you, mix a 50/50 solution of water and bleach and spray it on the coils as well. The bleach will eliminate most, if not all of the smell of the coil cleaner. Also pouring a 1/2 cup to 3/4 cup of the 50-50 solution in the drain pan will also help the smell, but is for the drainline and keeps it clean of bacteria, germs and odors. It also helps prevent clogs. For the homeowner, there's nothing simpler than using a foaming aerosol spray to clean your a-coil.