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Single Room AC

Single Room AC

Is there a room in your house that you don’t use too often because it’s either too hot or too cold? Maybe you have a room inside your home that doesn’t get warm or cold enough? If your answer is no to each of these questions, then lucky you. But if you answer yes because you can relate to these situations, then you know how bad it is and how worse it could get.  What you grapple with are hot and cold spot issues, and you’re not alone trying to tackle this problem.

Despite the amazing ways that air conditioners do to keep us warm or cool inside our homes, it seems always never enough. While our conventional comfort solutions, like a centralized AC system, work great to condition our indoor spaces and make us feel comfortable, there will always be a room that gets hotter or colder than the rest of the house, especially during specific seasons? This leads us to ask: What is the best air conditioner for a single room? Here is a quick table breakdown:


Easy Installation
Easy Setup
Flexible Application
Unrestricted Use
High Energy Efficiency
Compliments your Central A/C
Space Saving & Portable
Advanced Technology
Low Upfront Cost
Precise Temperature Control
Requires Vent
A/C & Heat Pump
Esthetically Appealing
Environmentally Friendly
Quiet Operation


Now let get into detail.


Thermostat Quarrels

With hot spots and cold spots creating unique comfort challenges inside homes and workplaces, it’s not unusual to find people wanting to wrest control over their comfort. It’s a fight so seemingly trivial that it is never talked about, yet this is the same desultory battle that many Americans so fiercely fought at one time or another—the infamous thermostat war. As people chase for the right temperature, the battle for thermostat control rages on. It happens inside many homes where altercation over indoor temperature pits spouses; and in offices where individual temperature preference makes for some cranky coworkers. As people come and go to crank the poor thermostat up and down, arguments get heated; relationships cool down—all because some prefer the indoor temperature just a little bit warmer while others want it a little bit colder.

Let’s face it, when it comes to our need for temperature comfort, hot and cold spots are posing a monstrous challenge. Interestingly, personal temperature preference is not even the problem. It’s the climate control system!

The Single Room Challenge

Temperature inconsistencies is a common issue, especially in homes that use central air conditioning systems. With a large area required to heat or cool, the system is usually strained and forced to work harder; but as most often the case, would not really achieve a hundred-percent heating or cooling due to various issues, such as leaky ductwork and poor insulation. As a result, some individual rooms get colder or warmer than the other parts of the house. The worst part is that your energy bill skyrockets and you can’t do anything about it because the airflow runs through one single, big duct network.


Ditching the Ducts

With unstable ductwork pointed as the common culprit behind temperature inconsistencies (alongside improper system size) that is typical in single room cooling and heating, it seems clear that doing away with systems that require ducts is the most plausible solution to effectively cool an individual room. Again, this brings us back to the question that we raised at the onset: What is the best air conditioner for a single room?

Customarily, window air conditioners and portable comfort systems are the more common solutions because they have been around the longest in the US. Next to central air conditioning systems, these two are widely used in many households in the United States. And of course, there’s the so-called ductless mini split system, an old, highly reliable solution for single-room application but only gained interest among homeowners and property managers in the country in the last several years.

What’s Your Best Bet for Single Room Cooling and Heating?

To find out which one best suits a single-room application, let’s take a look at these three single room air conditioners, gain insight on what they are, explore their unique features, and outline their advantages and disadvantages.


Window Air Conditioners

Also called room air conditioner, a window air conditioner is the simplest, most familiar, and common type of air conditioning system. If there’s any system that is exclusively designed for a single room, this is it—a cooling solution in its most typical, conventional form. Keep in mind that a window air conditioner is a self-contained unit, which means every component of the air conditioning system—whether it’s the compressor, the condenser, the evaporator, the fan motor, the cooling coil, and others—is assembled and integrated in one place and housed in one casing. Being a single-packaged air conditioning unit, the window air conditioner is a unitary system.

As for the advantages, a room air conditioner is known for being:

  • Easy to install - It fits anywhere in the room. Typically, it is mounted in a window or placed through a wall.
  • Flexible application - It can be placed in any single room, whether this room is within your home or detached from the main house.
  • Complements your centralized AC system - It works best as your alternative cooling solution, specially when the detached room that you want to cool (like a garage, for example) is not within reach of the main ductwork, which is typically concentrated in the main house.  
  • Highly affordable - The cost of a room air conditioner varies according to size, brand, capacity, and features.

Nonetheless, it still costs less up front than any other systems. The cheapest that you’ll find are priced at less than a hundred bucks, while the pricey ones cost can cost up to $700. If you put in the equation the installation cost, more or less it would only cost you within the range of $700 to $1,000.

When it comes to disadvantages, the drawbacks that are commonly seen with window air conditioners are the following:

  • Not so energy-efficient - Window air conditioners are known energy-hogs. If you’re going to use this regularly, then expect some considerable spike on your energy bill.
  • Can only cool a space at a certain degree - Designed for small rooms, a room air conditioner will only work best if you use it to cool an area that is appropriate to its size. Nothing more and nothing less. It cools a room not quite as fast as the other systems.Window air conditioners, after being turned on, usually takes time to cool the entire room.
  • Not aesthetically appealing - If you value room design, then a room air conditioner will be an issue. With its typical bulky appearance, the room air conditioner will not be quite pleasing.  Additionally, if you live in a community with a Homeowner's Association, odds are good window units will not be allowed.
  • Noisy operation - Most room air conditioners are typically noisy and you would really hear a bit of annoying noise because the condenser, the fan, and other internal components that make sound are housed together as a single unit.

If you choose to use a window air conditioner, don’t forget size as a major consideration. A too-large or too-small room air conditioner is impractical, costly, and can seriously affect your comfort experience. To find the right size of a room air conditioner for any particular room, it pays to ask guidance from your hired HVAC contractor.

Portable Air Conditioners

Like window air conditioners, a portable air conditioner is also a self-contained unit. It is typically placed on the floor and can be moved around. It works to cool your room by exhausting the warm air and moisture indoors through the use of a window kit or a drain hose. Some models have removable container where the water from the moisture is collected. You can discard this condensate water manually.

The main advantages of a portable air conditioner are the following:

  • Cools and humidifies air - Portable air conditioners work both as a cooling system and a humidifier.
  • Easy to setup - You don’t really install a portable air conditioner in the stricter sense of the word; you set it up. A unit usually comes with a kit, which guides you how to set up the whole unit.  
  • Unrestricted use - Best to use if, structurally, there’s no way that you can install a window air conditioner or for whatever reason (a building regulation, for instance) you’re not allowed to install one.  
  • Space-saving - Their small size makes portable air conditioners ideal to use even in small rooms with a very limited space.  
  • Low-cost cooling solution alternative - Portable air conditioners are not pricey compared with other advanced systems. They can also serve as a supplement to your existing HVAC system. 
  • Portable - You can bring a portable air conditioning unit anywhere, which is great if you need a cooling system for another room that you’ll have to use.

On the other hand, the main advantages of a portable air conditioner are the following: 

  • Limited cooling - A portable air conditioner can’t really cool a larger area. It is only designed to cool the surrounding space, that’s why most people who tried this system tend to use fans to let the cooled air get circulated in a far wider area within the room.
  • Requires vent - Portable air conditioners have to release the exhaust heat that it discharges. This means that a vent system is an important component.
  • You’ll need to constantly drain water - As humidifiers, portable air conditioners humidify moisture which results to the accumulation of condensate water. Constantly draining this water, when done in a regular basis, becomes physically taxing.  
  • Not so energy-efficient - When compared with other systems, portable air conditioners are not as energy-efficient.  
  • Noisy operation - Most portable air conditioners are a little bit noisy when in operation.

Keep in mind that portable air conditioners have limited capacities and only best to use as a supplementary cooling system. However, as long as a portable AC system works for you and meets your specific needs and requirements, then you would find this system just as excellent as the others.

Ductless Mini Split System

As the name suggests, a ductless mini split system is a compact unit that doesn’t require the costly and often complicated duct network. It is a split system owing to its component design, which is characterized by having an outdoor condenser unit and one or more indoor evaporator units called air handlers. These units are connected by refrigerant lines, condensate drain line, and the power cable. These wiring and piping systems are passed through a small conduit in the wall, enabling you to connect the two main units together.

If we examine the ductless mini split system, some of its many advantages are the following:  

  • Works both as an A/C and heat pump - Ductless mini split air conditioners can cool or heat depending on your chosen mode of operation. This particular feature makes the system as an ideal all-season, all-weather comfort solution.  
  • Precise temperature control - Ductless mini split systems provide zonal climate control capabilities, which means you can install different air handler units to different rooms inside the house and control/manage these temperatures independently of each other.  
  • High energy-efficiency - Most ductless mini split systems are designed with higher energy-efficiency than the other systems. Aside from high SEER and Energy Star ratings, they are built with energy-saving components and functionalities.
  • Advanced technology - Many of the ductless mini split systems that you’ll find today are highly advanced and feature cutting-edge components, smart functionalities, and intelligent control system, including remote access and mobile control.
  • Easy to install - The absence of duct requirements makes a ductless mini split system one of the most installation-friendly climate control system.
  • Cost-effective - Ductless mini split systems may require higher initial cash outlay during your purchase, but the higher savings that you would get in the long-term out of their efficient energy-use and energy-saving functionalities will be more than enough to compensate for this amount.  
  • Whisper-quiet operation - Ductless air conditioners operate quietly, mainly due to the fact that they are designed with the compressor/condenser unit completely separated from the air handler/evaporator unit.  
  • Unobtrusive design - As compact units, the indoor air handlers of a ductless mini split system are designed unobtrusive. They can be installed anywhere in the house regardless of interior design or aesthetic considerations.  
  • Environment-friendly - Ductless mini split systems use the non-ozone-depleting refrigerant R410A (Puron®) and they typically consist of recyclable components. Despite their excellent features, functionalities, efficiencies, and overall capabilities, ductless mini split systems are not perfect, just like any other system.

They have their own share of drawbacks, which include the following: 

  • Higher upfront cost - Ductless mini splits systems are a little bit pricey compared with the other systems. On the average, you will need an amount which is at least in the north of a thousand bucks to get a decent ductless mini split system.  
  • Installation cost may go upward - If you need it for a larger type of installation, you might need to purchase a few more air handling units that match the compressor. In other words, the cost might go upward depending on your needs or requirements. 
  • It requires professional installation - Ductless mini split systems may be easy to install, but they require qualified installers who are skilled and knowledgeable enough to handle the system. 

If you’ll choose a ductless mini split system for your single-room application, you will need to hire a professional HVAC contractor. Keep in mind that any installation error will have a huge impact on the reliability, efficiency, and performance of your mini split unit.

So, what to choose?

Choosing the right air conditioner for a single-room is not a straightforward decision. Remember that everything boils down to your specific needs and situation. Nevertheless, to be able to effectively determine the best choice, we’ll need to compare your different options by looking at how they fare when it comes to the following:


When it comes to energy-saving capabilities, the ductless mini split system definitely comes out on top. Coming in second are window air conditioners because they are also Energy Star rated. Portable ACs are typically non-regulated, and this makes them the least energy-efficient.


In terms of purchase price, the window are conditioners are the most affordable among the three. The most expensive are the ductless air conditioners, owing to their high upfront and installation costs, although there are affordable options. These costs make the portable air conditioners more expensive than window ACs but more affordable than ductless mini split air conditioners. Take note that price is also determined by the size of the unit. Portable ACs generally come bigger in terms of Btu than room air conditioners, and therefore more expensive. Initial purchase price, however, is not the right gauge. With a ductless system, for example, while you might have to pay more initially, it consumes less energy and therefore more cost-effective than the other two. In the long-term, the savings that you’ll get from low-energy consumption will be more than enough to cover or pay back the amount that you paid for the system.


Designed with better technology, ductless mini split system is no doubt the runaway winner in this aspect. You can also add the fact that a mini split unit is capable of cooling and heating a single room, which gives it another big advantage over the other two.


All three appears equal in terms of flexibility, although you will have to give it to ductless mini split due to its more expansive application. As a zonal system, ductless systems can be installed with different air handlers for different single-rooms using just one compressor. The precise cooling/heating capability is also a huge plus.

The Verdict: Ductless Mini Split is Your Best Bet for Single-room Cooling and Heating

It is worth noting that a ductless mini split system was originally designed as an upgrade to the older window air conditioners. Primarily, this technology was envisioned as a great workaround to the unique cooling challenges in which traditional systems were proven ineffective as a solution. With spot cooling as its main approach, ductless mini splits are indeed breakthrough systems that significantly offer answers with regard to the limitations and constraints that are typical in residential or commercial cooling and heating practices.

Providing targeted cooling/heating, ductless mini splits now resolve issues that are related to unbalanced temperature, unattainable ductwork expansion, need for higher energy-efficiency, cost considerations, demand for better temperature control, and many others. While window air conditioners and portable AC systems are unique and effective in their own ways, there’s no doubt that ductless mini splits rule when it comes to single-room spot cooling/heating. With no need for ducts and with their more technologically advanced components, ductless mini splits enable you to reclaim so many spaces that are otherwise unlivable due to temperature issues.



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