Here in Atlanta and North Georgia it seems like we go straight from winter into summer. For a few short weeks, the temperature fluctuates between cold enough for a jacket and hot enough for ice cream. Then, all of a sudden, we’re sweltering in the heat of Georgian summer. This can make heating and cooling during those in-between weeks a tricky balancing act. But before you start up that air conditioner for the hotter months there are a few maintenance issues you should take care of. If you maintain your air conditioner you can save on energy costs and avoid a sudden breakdown.
How an Air Conditioner Works
Air conditioners were first invented in the early 20th century. But they weren’t intended to control temperature. Instead, they were built to control humidity. The cooling was just a side effect. It wasn’t until the 1960s that air conditioning came into widespread use for cooling homes and businesses.
On the simplest level, an air conditioner works by absorbing heat from the warm air in the house and then releasing that heat outdoors. The way the heat travels is in a chemical called a refrigerant. The refrigerants used in residential air conditioning systems are hydrochlorofluorocarbons (HFCs).
What makes HFCs so useful as refrigerants is that they can go from vapor to liquid very easily. When the refrigerant enters the home in its liquid state, it absorbs heat for the home and becomes a liquid (just like boiling water that becomes steam when heated). The vaporized refrigerant is piped outdoors, where it is forced back into a liquid, which releases the heat and prepares the refrigerant to go back into the home and absorb more heat.
The Process of Air Conditioning
An air conditioner has four basic components: an evaporator, a compressor, a condenser, an expansion unit.
The evaporator is contained in the home. Hot air from the home is blown by fans across the evaporator coils. The liquid refrigerant in the evaporator absorbs the heat and is transformed into a gas. In that process, it removes heat from the air.
When the heat is removed from the air and the air cools, it can’t hold as much moisture. On humid days, the moisture in the hot humid air condenses on the coils and pools in the unit. From there it is directed into a drain. The air is now not only cooler, it is also dryer. This is why the unit is not just called an “air cooler”, it is an “air conditioner”. That’s because it conditions the air to be cooler and drier. This creates a much more comfortable atmosphere inside the home.
Once the heat from the air in the home has been transferred to the refrigerant, turning it into a vapor, the vapor is transferred to the compressor, which is housed in a unit outside the home along with the condenser. As its name implies, the compressor uses pressure to compress the vaporized refrigerant. As the pressure is increased so is the heat (just like in a pressure cooker).
From the compressor, the hot vaporized refrigerant passes into the condenser. In the condenser, the heat is radiated away and the refrigerant condenses back into a liquid. Often a condenser will have fins. The fins allow more air to pass over the refrigerant which allows it to radiate more heat and cool more quickly. A fan blows are over the coils to increase cooling. The refrigerant can now be pumped back into the house for another go around of cooling.
The expansion device regulates how much liquid refrigerant enters the home.
Preparing Your Air Conditioner: A Checklist
Before you turn on your air conditioner for the summer, it’s good to go through a brief check to make sure are getting the most out of your air conditioner.
1. Do a visual inspection of the outdoor unit: The outdoor unit contains both the compressor and the condenser, as well as a large fan. It’s important to make sure that the protective covering on the outdoor unit is secure and in good condition. If the covering is loose it could be dangerous for people and for the unit. If the protective covering is damaged at all, call a professional to repair it.
2. Check the suction line: The suction line is the large copper pipe on the outdoor unit. It returns cool vaporized refrigerant to the compressor, where it is compressed and heated. This pipe should always be insulated to maintain a cool temperature. If the insulation comes off, the refrigerant can become overheated and damage the unit when the compressor heats it further. Over the winter the insulation can easy be damaged. If the temperatures drop below freezing, the insulation can freeze and thaw, causing cracking. The sun can also damage the insulation. Sometimes small animals or bugs seeking shelter from the cold may try to get into the insulation. If there is any damage to the insulation it must be replaced before you turn on the air conditioning unit.
3. Remove anything blocking the condenser coil: The condenser could is where the heat the refrigerant picks up the indoors is radiated back out into the air. If the coils are blocked or the airflow is in any way reduced, the refrigerant can’t properly cool. This could reduce the cooling capacity of your unit or even cause damage. For the best performance of your air conditioning unit make sure that the area around the outdoor unit is clear. Don’t mulch around the base of the unit. Be careful if you are putting anything around the unit to hide it that you are not blocking the airflow.
4. Replace your air filter: It’s important to replace your air filter regularly to keep your duct system—and your home—free of dust and debris. The change of seasons is a good time to check and replace your filter. Here in Georgia, you may find yourself running your air conditioner almost constantly. Under those conditions, it is recommended to change your air filter almost once a month (unless manufacturer’s instructions say otherwise). This is especially important in the Atlanta metro area where we have extremely high pollen levels.
5. Clean supply vents and return grills: Like changing your air filter, this should be done regularly, but the change of season is a good time to do it again. Use a vacuum to clean dust and debris from the supply vents and return grills that send air to and from your air conditioner unit. It also important to make sure that both supply and returns are not blocked by furniture or anything else, so that you can get the maximum efficiency out of your unit.
6. Check the evaporator drainage hose: The evaporator will collect condensation on the outside of the coil. This is great because it makes the air in your home less humid. All that condensation drips down into a tray. If everything is working right, there should a plastic pipe that drains the tray. Make sure the pipe is in place, not clogged, and drains to the correct location. This will avoid overflows or other water damage.
Maintain Your Air Conditioning Unit
Regular maintenance of your air conditioning system will keep it functioning at its best. Many companies offer regular maintenance packages, and it’s a good idea to contract with w reliable company to maintain your system. TrustDALE partners with the HVAC providers, all of whom we know you can: Coolray Heating and Cooling, Shumate Air Conditioning and Heating, and R.S. Andrews Heating and Air. With these companies, you can be assured top-notch service and fair, affordable pricing. Their technicians are factory trained to work on your system.
As winter quickly turns to summer, contact one of our TrustDALE partners to get your air conditioning system ready to go!