What is AC Short Cycling?

May 20, 2020

During the summer months, your thermostat starts reading higher temperatures. When it does, it will tell your air conditioner to turn on so that your home is cooled. If the temperature you have set is not reached before your unit turns off, there is an issue. This is called short cycling. There is something in your system stopping your air conditioner from finishing the cooling cycle.

A complete cooling cycle begins when your AC unit turns on. Once your house has reached the temperature you have set your thermostat at, your system turns off to complete the cycle. This cycle is what enables you to remain cool and comfortable in your residence. When your unit is constantly turning on and off, your energy bills will be noticeably higher, and your air conditioner will wear out prematurely.

The refrigerant in your AC unit is what absorbs the heat from the air in your residence. This heat is then sent outside. Your compressor is very important because it is how the refrigerant is compressed and circulated throughout your system. Your compressor must be on for the cooling cycle to complete. During an average summer day in the state of Washington, our team at Brennan Heating & Air Conditioning sees approximately three cooling cycles every hour. About 10 minutes is required to complete each cycle.

During a cycle, your compressor runs for 10 minutes and stops for another 10. This cycle is normally repeated another two times in the course of an hour. When your cycle does not last for 10 minutes, your compressor will keep turning on and off. Not only will your compressor experience excessive wear and tear, but your house will also fail to cool appropriately.

The Causes of Short Cycling

We have seen several issues that result in short cycling. One of the most common is an air conditioner that does not have enough refrigerant. Unfortunately, this can be a contributing factor to other problems, including ice buildup. If your thermostat is incorrectly placed, the heat from lamps or uncovered windows may cause your unit to turn on when cooling is not necessary. This also causes short cycling. The issue may be the low-pressure switch responsible for turning off your system at the correct times. If you have older equipment, this part may be failing. That frequently results in short cycling as well. It is also possible that your air conditioner is simply oversized.

The most common reasons for short cycling are defined below. You will be able to handle some of these issues yourself, including replacing a clogged filter. Others will require a professional technician to ensure a safe and effective repair.

Your Air Filter Is Clogged or Dirty

You should be cleaning or replacing your filter on a regular basis. The frequency depends on your air conditioner and your circumstances. When your filter is dirty, your unit is forced to work a lot harder than necessary. Microscopic particles of dust, dirt, and detritus cause your AC to labor too hard in an effort to compensate for the decreased airflow. This increases stress on the parts responsible for the operation of your compressor and blower. The components impacted can make your unit short cycle. It can even break down completely, leading to an expensive repair. We do not want you to be without air conditioning during the summer, even for a fairly short period of time.

Your Air Conditioner Is Oversized

If your unit is too large for your home, the air conditioner will cool too quickly and turn off. The cooling in your house will be uneven, you will need additional maintenance, and your energy bills will be a lot higher than they ought to be.

Your Refrigerant Level Is Low

When your refrigerant level is too low, your unit will be unable to cool your residence properly. The result is increased stress on numerous components. Your unit is forced to work much harder, and it will start and stop irregularly.

Your Evaporator Coil Is Dirty or Iced Up

We see this issue often when the air conditioner has not received routine maintenance on a regular basis. The hot air in your home is removed by the evaporator coil. When the coil is functioning incorrectly, your unit works harder to remove this air. The result is that your air conditioner overheats and turns off.

The Impact of Short Cycling

Short cycling will impact both your air conditioner and your monthly energy bill. The most common impacts we have seen include the following.

Loss of Energy Efficiency

When your air conditioning system is working correctly, your home is cooled gradually in long cycles. This is how your house reaches and maintains your desired temperature. During a longer cycle, the proper amount of cold air circulates throughout your residence. If the process is not both thorough and slow, your unit will be unable to run efficiently. When your air conditioner is short cycling, there is a constant battle between air that is too hot or too cold. If short cycling occurs for too long, your air conditioner will be placed at risk.

The Risk of Failing to Repair Your Unit

Once your system has been operating inefficiently for a while, the issue will eventually become worse. There are two reasons this occurs. The first problem is the actual short cycling. Since your unit is working constantly, your system becomes strained. Components such as bearings and fans will wear out. This leads to even more problems with your AC.

The second issue concerns whatever is actually responsible for the short cycling. A good example is a refrigerant leak. Your compressor will be forced to work a lot harder. If you do not have your air conditioning system repaired, your compressor will eventually burn out. If this happens, you will need to have your compressor replaced. This is a significant expense that can be avoided.

Your Air Conditioner Should Be Replaced

We do not like to tell any of our customers their AC unit is beyond repair. The good news in some cases is that the problem is simply a dirty filter or a faulty thermostat. However, if your system does require replacement, the newer models available are more energy-efficient. This means it will cost you less to cool your home. If your air conditioner is short cycling, we recommend checking your filter first.

When your filter appears dirty or clogged, either clean or replace it. If your unit starts functioning correctly, you have probably fixed the issue. If your unit continues short cycling, however, you may require technical assistance. We do not recommend attempting to repair the unit by yourself. Professional technicians have been trained to fix your equipment safely and efficiently.

If you try to repair your air conditioner, you may inadvertently make the problem worse. Having your unit serviced every year will not only help to prevent short cycling but also stop a lot of other issues from developing. When you know your home is cool and your family is comfortable, you will have the valuable gift of peace of mind. Our customers also appreciate receiving the lowest utility bills possible.

The Importance of Service and Maintenance

At Brennan Heating & Air Conditioning, we understand the importance of properly maintaining your air conditioner in Seattle, Tacoma, or a surrounding area. For this reason, we offer maintenance, installation, and repair services for both cooling and heating equipment. We also provide a complete array of electrical services, install water heaters and heat pumps, conduct diagnostics, and perform air duct cleaning. Call us today to make certain your air conditioner performs properly throughout the Washington summer.

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