Air Conditioner running constantly: How to prevent it!

Returning to the comfort of an air-conditioned home is an experience many enjoy, especially during hot, humid weather. However, in some instances, you may notice that your air conditioner seems to run constantly once turned on or is working harder than usual. You may wonder if this is normal, or is it a sign that your air conditioner could be in need of repair? 


In this article, we will explore what can cause an air conditioner to run constantly, and their solutions. Some are easy fixes, others can be solved by routine maintenance, while others may need the intervention of an expert.



Is it normal for the AC to run continuously? 

Typically, under regular circumstances, an air conditioning system runs in cycles. The cycle begins when you turn it on, and ends when it reaches the desired temperature. Inverter models can keep running at lower power, to maintain the temperature and reduce the need for running a cycle very often, helping save energy.


It can be normal for your air conditioner to cycle often or for longer when there is a great difference between the outdoor and indoor temperatures, as the AC has to work more often, and harder to maintain the desired setting. This usually means that setting the temperature to a more efficient value will make the AC run normally again. Find out what’s the ideal AC temperature to balance comfort and energy consumption here.


Another situation that makes the air conditioner cycle continuously is an open door or an open window that prevents the room from getting to the set temperature. Check for any openings that are letting the conditioned air escape too quickly and your AC should run fewer cycles.


If the AC runs continuously even if the outside weather is not too extreme, or runs non-stop no matter what, you may need to check for an underlying issue.




Why should you be concerned if the AC runs constantly?


When the AC malfunctions, either for any of the reasons below or another unknown cause, it should not be ignored. When this issue is left unchecked, you may face other issues arising from it:

  • The AC isn’t as effective. The main reason for the AC is to provide comfort at home, but when it starts malfunctioning, it becomes less effective and unreliable, and it doesn’t fulfill its role.
  • Higher energy consumption. It goes without saying, the more the AC cycles, the more energy it consumes. Modern AC systems are more energy efficient than older models, so an AC doesn’t necessarily mean high electricity bills, but it should be maintained properly.
  • Deterioration and damage to components. The cost for servicing a minor issue in the AC can be an inconvenience, but many unresolved issues can cause further damage to the appliance, reducing its lifespan.



Why does your AC keep running constantly?

There can be many reasons for the AC to run cycles abnormally, let’s take a look at the most common ones:

  • Clogged air filters. The AC’s filters have an essential role to keep dust and particles away, improving indoor air quality, and letting clean air flow through. The issue is that they can get clogged when they have too much debris or dirt trapped, and airflow becomes much more restricted, meaning your AC has to work harder and longer to reach desired temperatures.
  • Dirty evaporator coil. The evaporator coil absorbs heat from the air that is blown onto it. Because of this, it is susceptible to dust build-up; and over time, it can become an issue, as the coil gets covered in particles, reducing the AC’s ability to cool, and causing it to consume more energy. You may even notice the AC blows warm air instead of cool air. This can also happen if the evaporator coil is frozen.
  • Clogged or leaky vents. Vents and ducts enable air to flow and allow the AC to run as it is designed to. When there are obstructions or leaks in the vents, air may not flow correctly, or it may even leak, preventing the AC from working properly.
  • Thermostat issues. The thermostat gives readings of the temperature, and thanks to it, the AC can stop the cycle when the temperature is adequate. In some cases, it is possible that the thermostat stops working correctly, and gives incorrect readings, thus not allowing the AC to stop the cycle even if the room has been cooled off.

  • Low refrigerant level. An AC’s refrigerant level can become low when there is a leak. The refrigerant is what enables the AC to cool warm air off, so if there is not enough, even when the AC runs constantly, it won’t get to the desired temperature.

  • Incorrect AC size. The AC’s size should be suitable for the room’s size and features. An AC that is too small may run constantly to cool a room that is too big for its capacity. And an AC that is too large is no good either, as it can waste more energy to cool a small space.



What if the AC outdoor unit is running continuously?

It may happen that it’s not the indoor unit that keeps cycling, but rather the issue is that the outdoor unit keeps running. It can be more difficult to notice malfunctions in the outdoor unit, as we look less at it, and thus do not think much about it. But some of the symptoms of an outdoor unit running constantly are also noticeable in the way your AC cools. It may not cool entirely, or you may notice it is not as effective as it used to be, or there is a sudden increase in its energy consumption.

  • Dirty condenser coil. In some cases, you may notice the outdoor unit keeps running even if the temperature indoors is adequate. This can happen when there is dust build-up on the condenser coil. The condenser coil releases the heat that is absorbed from your home’s air. As it is in the outdoor unit, it is more susceptible to external factors. Not only dust and particles, but rainwater, frost, and insects can also get in between the outdoor unit’s components. Dust and dirt covering the condenser coil prevent it from letting the heat disperse, and thus the outdoor unit keeps running.




How to prevent the AC from running continuously?


Many of the causes listed above are easily prevented by maintenance checkups. The aim of preventive maintenance is to keep the AC functioning smoothly for as long as possible. It reduces the need for repairs and replacement of components that could have been saved if serviced sooner. These are some of the routine maintenance tasks that prevent issues down the road.

  • Filter maintenance and cleaning. Fortunately, this task can be easily done by yourself, if you closely follow the appropriate directions. Keeping the air filters clean will not only let the AC run better, but you will also notice improved indoor air quality. For more information, read this article, where we have compiled the instructions to safely clean your AC’s air filters.

  • Routine cleaning and checkup. You can perform a basic checkup by cleaning the outer casing of the AC unit with a damp cloth to remove dust. And look for any obstructions around the vents, leakage, or unusual noises or smells. Remember to do this both for the indoor unit and outdoor unit.

  • AC unit maintenance. This is a task a professional should perform, as they will not only solve any issues that need immediate attention, such as cleaning the dirty condenser and evaporator coils, but also find any irregularities that could be overlooked if not observed with expertise.

  • Duct maintenance. Usually, if the AC’s installation is properly made, the system’s ductwork will remain optimal for years, as filters keep particles and debris out. Most of the time, the only maintenance ducts need is a checkup to see everything is in order and some occasional cleaning.  But sometimes, ducts can present leaks that need to be caulked, or they may need to be insulated if extreme weather conditions affect them. In any case, an expert’s advice is needed for ductwork maintenance.

When do I need to contact a professional?

When routine maintenance doesn’t prevent malfunctioning in your air conditioner, it may be time to call a professional technician. AC repair work may be the only option if you have a faulty thermostat or refrigerant leakage. An expert can help you fix the issue at hand and give you advice on the next steps.

It is also necessary to note the importance of contacting a trusted professional for the installation of the air conditioning system. An optimal installation can save you money in the long term, as a trusted technician will use their expertise to make an efficient and adequate installation for your home’s needs. For example, if your AC’s size is incorrect, the only way to solve the issue is to replace it. This expense could have been avoided with the advice of a trusted professional, who takes into account your home’s size, ceiling height, sun direction, insulation, and other factors, to recommend an AC with the correct capacity.

Find out more about AC sizes, tonnage, and other capacity terms you may find when looking at AC models.




Hitachi Solutions for the ideal AC experience

We have seen that preventative maintenance is key to smooth AC functioning, as well as proper AC installation. No matter what your home’s cooling and heating needs are, you can find the perfect solution for you in the range of Hitachi Residential Air Conditioners.




Where can you find us?

Let our team of experts guide you through our Residential Air Conditioning ranges, or get assistance from the technical support team for preventive maintenance.

Contact your local Hitachi Installer using our Dealer finder, or if you are in need of a commercial air conditioning solution, use our Contact form to get in touch with our Hitachi sales team.



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