How to Make Your AC Colder in Your House?

how to make air conditioner colder

Your air conditioner may have worked strongly in the years since it was purchased, but even after a short time, you can notice there is a significant decline in its efficiency. With this in mind, you may wonder whether you got the right type and model of air conditioner, as well as how to restore it to its previous state of glory. This is exactly what we will be covering here. 

The thing is that an AC unit or an air conditioner is in its best state right after the purchase. As you use the unit, many problems can arise, but luckily, they are easy to solve. Dirty filters can be removed, refrigerant leaks can be handled, and leaky ducts can be fixed. The situations that would demand you to purchase a new air conditioner are few, and they typically arise after 10-20 years of useful service life. 

With this in mind, it is easy to conclude that a well-maintained air conditioner will last longer, will be able to deliver colder air, and will cost less to run. Every cooling system demands regular upkeep, and your air conditioner is no exception here. Now, let’s go and consider all the advice we have in more detail. 

How to Make Air Conditioners Colder?

Making your air conditioner colder or making it expel colder air will easily add to the quality of your life. Who does not like returning to a cool home after a long day at work? However, doing so without using more energy and with good control over your energy bill is the key. Besides a home energy audit, there are more things to consider doing: 

  • Clean and change the air filter as needed, 
  • Conduct regular AC maintenance or call in a professional to help you, 
  • Use blinds and heavy curtains to keep direct sunlight out of your home, 
  • Check the air seal around your window air conditioner, 
  • Use fans to help you cool your place faster and circulate the cold air, 
  • Check thermostat placement with the central air conditioner, 
  • Prevent short cycling by choosing an appliance with the appropriate cooling power for your home size, 
  • Use the right refrigerant
  • Spray down the AC unit to clean dirty coils (condenser coils), 
  • Consider the AC location, both indoor and outdoor unit, 
  • Turn off electronics and other appliances, and 
  • Replace an old air conditioner. 

Clean/Change the Air Filter

Cleaning or changing the air conditioner’s filter is the first step to a more energy-efficient air conditioner and to avoiding higher energy bills. Reduced airflow through a dirty air filter will influence the efficiency of your unit, making it work harder and use more energy for the same work. Make sure to clean only filters labeled as ‘washable’ and be careful about the installation direction – there is usually an arrow indicating the desired airflow that you may find useful. 

Conduct Regular AC Maintenance

Regular AC maintenance includes both the work that you can do and that professionals should do. Once a month, you should clean the air filter to allow your air conditioner to run colder. Besides this, there are filters in the internal units as well, and they should be cleaned to both remove dirt and debris as well as to avoid promoting mold and mildew growth. 

Use Blinds or Heavy Curtains

Using blinds or heavy curtains will help you keep sunlight out of your home. Although sunlight cannot reduce the efficiency of your air conditioners, it can keep heating your home, making it more difficult for the AC to reach the desired/set temperature. This way, you can use less energy during the summer and save money – all by simply keeping light out. 

Check the Air Seal

The air seal around your window AC will perform the same function as the layer of insulation around your home would – it will keep the hot air out and the cold air in. This way, you will be able to have less draft and spend less energy to keep your home at the desired temperature while at the same time expanding the useful lifetime of your AC unit – since it does not work harder than it should. 

Use Fans

Using fans may seem counterintuitive, but making the air circulate around your home will make it cool the house faster. As the cold air enters your home, it will be dispersed throughout all rooms and entire rooms with little extra energy used. In return, you will be able to up the temperature setting by up to 4 degrees without spending more on running your AC units. Ceiling fans serve the same purpose, so make sure you keep them on during the peak cooling times of the day. 

Check Thermostat Placement

Your thermostat is a small device that measures the air temperature in your home and ensures that your AC units can do their job. This useful piece of tech is an integral part of the air conditioning system, and the AC relies on it for correct temperature readings. Placing the thermostat away from any sources of draft, sunlight, as well as heating or cooling bodies will make your conditioner colder and your home more comfortable. No more surprises upon reentry into your own home. 

Set Thermostat to a Constant Lower Temperature

Setting the thermostat to a lower temperature will make it run in longer cycles and will help keep your home temperature more stable and lower during the summer. However, any temperature under 78°F will make your AC run extra hard, while any temperature under 85°F when nobody is at home is a sheer waste of energy. Use a programmable or smart thermometer when needed and ensure that you use just the right amount of energy. 

Prevent Short Cycling

Short cycling happens when your air conditioners come on and off too often. To prevent this, you should choose the right size of air conditioning unit for your air conditioning needs. A unit that is too large will typically short cycle, while a unit that is too small will keep running all day long and may not even be able to reach the ideal temperature during the late summer months. A unit of the right size will typically be more efficient, irrelevant of your house size. 

Use the Right Refrigerant

Using the right refrigerant is the next best thing to do to ensure efficiency and to keep your air conditioner colder than the surroundings. Older refrigerants were not as efficient at conducting heat and used more energy. Besides energy efficiency increases, newer refrigerants are also much more eco-friendly and may help you save money. 

Spray Down the AC Unit

If you do not feel cooler even after the AC has been working all day on a hot day, it may be time to spray down the AC unit. This is typically done on the outside unit, while the inside unit should only be sprayed by a professional. This will keep both the condenser (the outside), and the evaporation coils (the inside coils) clean and will help them work more efficiently. 

Consider the AC Location

Consider the location of both the inside and the outside of your AC. To make your air conditioner colder and to keep it running smoothly, both units need to be placed exactly where they should be. The indoor units are typically placed away from sunlight, and you need to choose the appropriate size for each room. Outdoor units are best placed in the shade, but beware that they will require regular cleaning from fallen leaves. 

Turn Off Electronics & Appliances

You have probably heard of vampire load. This is the load that all the appliances that are plugged in, although they may not be working, draw from the main panels. And as soon as they do, they produce small amounts of heat. This heat can add up, making your AC work harder than before while having difficulties keeping your house cool. 

Replace Old Air Conditioners

If your C is not as cool as it once was, and if you have issues keeping the room cold, it may be time to start looking for a new AC. To make your air conditioner last longer than usual, you should keep all the units clean and dust-free and perform regular monthly and annual maintenance. Only this way will you be able to actually keep it for the projected 10-20 years of its lifetime. 

Central AC vs Window Type AC

When we discussed how to make your air conditioner colder, we mentioned window and central units. It is important to know the difference between the two types of units and to know about the pros and cons of each type. With this in mind, let’s begin. 

The central units are bigger, more durable, and have a higher cooling power. On the other hand, they are also more expensive. Keeping these units clean means cleaning both internal and external coils and filters, as well as taking care of the grasses, weeds, and potential leaf buildup on the outer unit. On the other hand, these units can cool entire homes at once, use less energy than window units, and may last for way longer. 

Window units are smaller and less powerful, but they cost less as well. These units are mounted on windows in your home and you can have as many as there are windows. Their biggest con is that they can cool only a single room, but if your home is small, using ceiling fans or a regular fan to disperse the cold air throughout your home is sometimes enough to help keep your house at a comfortable temperature. When you circulate air, any AC will be more efficient, as cooler air will be found in more than one room and in more than a single spot. 

Common Problems if the AC is not Cooling Enough

Irrelevant of which type of AC you may choose, there are certain problems that can happen and steps that you can take to make your air conditioner run colder. Common issues that may prevent it from doing so include a dirty air filter, airflow issues, and an AC that is not the right size for your home. 

Dirty Filter

A dirty filter is simple to resolve to make your air conditioner run colder. Simply wash or clean your air filter. Beware that they all have their useful life and that filters found in most air conditioning systems will need to be replaced after a while. Simply purchase a new air filter, ditch the old one, and see how reduced airflow becomes a thing of the past. 

Airflow Issue

Besides a dirty filter, furniture, and closed air vents can also cause airflow issues. This means that your air conditioner will work less efficiently and will take longer to beat the outside heat. To prevent this, keep all vents open, clean them regularly, and make sure to avoid placing anything on top of them. 

AC Not Appropriately Sized for Your Home

Another common issue that can be seen is that the AC unit size is not the right size for your home. If the unit is too small, it may need more time to cool the place down which may result in higher energy bills. No switching of the filter regularly can help here. If the unit is too big, it may start and stop too frequently, causing short cycle issues, a common culprit behind many breakages of the AC units. 

Possible Causes if an AC has Stopped Cooling

how to make an air conditioner colder

So, an AC may need to be checked regularly to make sure it works right. But what to do if it stops working altogether? Here are some possible causes if your AC has stopped working: 

  • A faulty thermostat, 
  • Wrong fan setting, 
  • Leaky ducts, 
  • Drainage problems, 
  • Dirty filters, 
  • Obstructed outside units, or 
  • A refrigerant leak. 

Faulty Thermostat

A faulty thermostat is one of the most common causes of a faulty or non-functioning AC. A faulty thermostat will give wrong readings, if any at all, and may prevent your AC from powering on. This is the first place to check, so check all connections behind the thermostat and any dust deposits on the air inlet of the unit. If everything is OK, go on to contact a professional who may be able to check/replace the unit. 

Wrong Fan Setting

Wrong fan settings can also cause a malfunction in the AC unit. They should be placed to AUTO, not just ON, and definitely not OFF. Some modern indoor ACs also have a silent or night mode. Although these modes generate less noise, they are not meant to cool down a hot room, let alone an entire house. Keep silent or night modes for the night only. 

Leaky Ducts

Leaky ducts may cause a variety of issues. Similar to faulty air seals, they allow cold air to escape so that your AC may not be able to cool down the place. Down the road, this makes the AC work way harder and longer than it should, decreasing its lifetime and increasing your monthly bills. 

Drainage Problem 

Every AC unit has a drainage hose and some models also feature a drainage pan. You should check this hose periodically. As it is always wet and humid, the chance of algae and slime buildup is really high. You should periodically check on this hose and clean it. If you are unsure how to do it, contact a local professional and let them do it for you. 

Dirty Filter

A dirty filter can slow down your AC and make it work extra long. To prevent this from happening, open and clean the air filter at least once a month. This should especially be done before the summer season. Another reason to clean/replace the filter is mold spores buildup, which can be quite dangerous for your health. 

Obstructed Outside Unit

An obstructed outside unit can cause issues of its own as well. The outside unit contains a condenser coil, which is where all the heat dissipated from. This unit should not be covered or obstructed in any way, as this may significantly reduce the efficiency of your AC. Also, it should not be placed in direct sun either. 

Refrigerant Leak

A refrigerant leak is a serious issue that you cannot resolve on your own. Refrigerant runs from a condenser unit and coils to the evaporator coils – this is how your home gets cooled down. If you have issues with a refrigerant leak, the leak has to be located, the crack in the pipes (similar to plumbing pipes) has to be fixed, and then, the refrigerant has to be reintroduced into the system. This is a complex task, and we strongly advise you to start looking for a certified professional to do this for you. 


How Do I Know if my AC needs Freon?

Your AC unit may need additional freon from time to time. Although ideally, this should not be happening, you should have a professional come to clean and inspect your AC unit once a year at least. If you can hear hissing or a bubbling sound from your AC unit, this may be a sign that you need to top off the Freon – make sure this is done by a professional. 

How Do I Know if my AC Unit has Low Freon?

If you can hear a hissing or a bubbling sound coming from your fridge, this may be a sign that your AC unit is low on Freon. There are also other ways to know: ice build-up on the pipes, your internal AC unit blowing hot or warm air, and very high energy bills. Always have your AC unit inspected once a year at least. 

What Happens if You Set Your AC Too Low?

If you set your AC too low, the unit will keep blowing all the time. This can be a very bad solution for many, as the AC needs some downtime as well. Making it run for too long can increase the amortization rate and can increase your energy bills as well – and neither is too good. You should also be able to know what temperature is good for you and your home to prevent mold and mildew and health issues that come with low temps and high humidity. 

Is it Normal for AC to Run All Day when Hot?

Usually, your AC should not run all day when it is hot outside. However, you should consider that your unit may be too small for the square footage you have and that your unit might be low on Freon. If your AC is running all day long, make sure to contact a certified professional to come and inspect the unit itself. 


A good AC will be the right size for your home, will be able to cool down the place in a matter of an hour or so, and will be energy efficient. However, many ACs use more power than is necessary and may not perform as well as they used to. Unless your unit is over 10 years old, our guide will help you clean and maintain your unit for a maximum lifespan. 

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