Window-Mounted Air Conditioner Buying Guide

Window-mounted air conditioning units are the most common type of air conditioners and have been used all over the world from the time after the World War II happened. It is widely used because it has the simplest form of AC system where the single unit is strategically placed on windows or through walls.

Compared to the recently developed and created split type ACs where the evaporator and condenser are located separately, window air conditioning units have both the evaporator and condenser on the same unit. It is just equipped with double shaft fan motor to help both the evaporator and condenser. An insulated partition can also be found inside which separates the two sides for more efficient cooling.

Getting to Know the Parts of a Window-Mounted Air Conditioner

Window-mounted ACs have three basic parts – the front panel, indoor side components, and the outdoor side components. Despite the revisions over the years to make window air-conditioners more energy efficient and quiet, these remain the three basic components. What differ though are the things in the indoor side components.

To give you a better idea of how a window air conditioner works in making our environment cooler and more comfortable especially during the hot summer days, let us get to know the three basic parts more:

  1. The Front Panel

This is what we instantly see whenever we see a window-mounted air conditioning unit. It is the one that faces the inside of the room and where all the controls are located. Older units usually have mechanical controls or rotary type knobs to adjust thermostat while newer units use a digital interface with either a touch panel or a remote control.

This is also where the louvers are customarily located. There usually are adjustable horizontal and vertical louvers so that users can direct the direction of the air flow for ultimate convenience.

In this front panel, the VENT or ventilation can also be found. Through this, a fresh intake of air can seep through.

  1. The Indoor Side Components

Listed below are the parts of a window-mounted AC inside where the process of air-cooling happens:

  • Image of window mounted air conditionerCooling Coil – This is exactly where the heat and cold exchange happens as the air inside the room goes through the refrigerant and cooling coil in the system, thus, producing the cold air. Cooling coils usually have air filters mounted on them so that the users are assured of a thoroughly filtered and clean air to breathe inside the room.
  • Filter Drier – This is responsible for removing moisture from the refrigerant.
  • Fan Blower – This is responsible for blowing the cold air out into the room. This is also referred to as the centrifugal evaporator blower.
  • Capillary Tube – This works as an expansion device which must not be located near the evaporator. If your window air-conditioning unit is quite noisy, you might want to have the location of the capillary tube checked.
  • Drain Pan – This holds the condensate water from the process of the air passing through the cooling coil. The water is then pushed out into the outdoor side part of the window air conditioner or the side that faces outside, hence, the water you usually see dripping outside of the unit.
  1. The Outdoor Side Components

Have you ever wondered why window-mounted type ACs usually blow hot air outside? The outdoor side is the part that is outside the wall or the window and cannot be seen from the inside. Its parts include:

  • Condenser Coil – This is the one responsible for rejecting heat from the refrigerant.
  • Compressor – This compresses the refrigerant and allows it to circulate under such pressure.
  • Fan Motor – There is a double shaft located at the outdoor side of the window air conditioner where the indoor and outdoor propeller fans are connected together.
  • Propeller Fan – This is an important part with regards to the condenser as this helps remove air molecules during the process of condensing roll.

The Things You Should Consider

Window-mounted AC units vary in capacity and capabilities. Some are designed to cool just one specific room with a specific size area while some have bigger capacities and can efficiently cool up to several rooms.

Some types are designed to be traditionally installed in the common double hung windows while others are designed to fit in walls or casement windows. Here is a short but complete list of the things that one must consider when shopping for a window-mounted AC unit:

  1. Cooling Capacity

What good will your newly bought window-mounted AC be if it cannot cool your room effectively? This is why you have to be knowledgeable about the different cooling capacities of air conditioners first and foremost.

Cooling capacity of all types of air conditioners is measured in British Thermal Units or BTU as is commonly seen in AC descriptions in the shelves today. A window AC with a low BTU does not suit a large room size. If you make this mistake, you will only end up paying more for your electric bill.

Just the same, a high BTU air conditioner will not cool the room efficiently but only leave it with uncomfortable hot and cold packets that would still translate to increased energy consumption. Check out the table below so that you will be properly guided in your quest for the perfectly suitable window-mounted AC unit.

Area to be Cooled (sqr feet) Power Capacity (BTU/hour)
100-150 5,000
150-250 6,000
250-300 7,000
300-350 8,000
350-400 9,000
400-450 10,000
450-550 12,000
550-700 14,000
700-1,000 18,000
1,000-1,200 21,000
1,200-1,400 23,000

In addition to those mentioned above along with our given table, there are also several factors that can affect the efficiency of a window-mounted air conditioner that must be understood. Check out these other but equally important factors as well:

  • Ceiling Height – Just like in other types of ACs, the table above applies to rooms with a standard ceiling height of 8 feet. However, any room that goes above this number warrants an adjustment in the power capacity.
  • Number of People – The numbers on the table above is applicable for rooms that will be occupied by a maximum of two persons. If there is more, it is right to adjust the power capacity and increase by 600 BTU per person.
  • Sunlight – Morning sun is okay. This is even good for one’s health. However, if your room stays sunny even during the afternoons, you should increase your power capacity by at least 10%.
  • Shade – If your room is pretty much covered by everything else around you and does not even see the rays of the sun, then it is safe to decrease the power capacity by as much as 10%.
  • Kitchen Use – Kitchen is the hottest area of every house. If you are shopping for a window air conditioning unit that is to be placed at the kitchen, it will be wise to increase the capacity by at least 4,000 BTU to be sure that the air conditioner will not be pushed to its limit and that the area will still be efficiently cooled even when someone is cooking.
  1. Energy Efficiency

Window-mounted ACs are generally classified as more economical than other types of air conditioners especially the central split-type ACs. They cost less and take up less energy, therefore, giving great savings in long-term usage.

Experts says that with regards to window-mounted AC units, there mainly are two things to look out for – Energy Star rating and the EER or Energy Efficiency Ratio. Basically, if you see an Energy Star rating, it automatically means that an appliance is ultimately energy efficient.

Energy Star (link) rating means that the unit uses 10% less energy than window ACs that do not bear the Energy Star seal. Therefore, this saves you a lot on operating costs while you get to enjoy more or less the same helpful features that give you and the whole household great convenience.

EER is another way to determine how energy efficient a window air conditioner is. It basically indicates the amount of BTU used for each watt of power, therefore, giving consumers a better idea of how much to allot for the electric bill. Experts say that the rule of the thumb is that the higher the EER, the more energy efficient the AC unit is.

  1. Electrical Requirements

Just like the other types of air conditioning units (portable and mini-split), the electrical requirement of a window-mounted AC unit depends on its capacity or BTU. If you plan to cool a relatively large room, then you need a window air conditioner with a higher BTU which would then require higher electricity.

In the United States, 110-120 volts is the standard circuit but this does not necessarily mean that all window-mounted ACs will operate on that electricity. Another rule of thumb here is that if a window AC unit has a BTU of 15,000 and below, then it can safely run on the standard residential electrical capacity of 110-120 volts.

But if you just bought a window-mounted AC with higher than 15,000 BTU rating, then you have to check the circuits in your house and make the necessary adjustments as these usually need to run on 220-volt circuits. In such cases, you need to seek the help of a professional electrician or someone who specializes in electrical wiring.

  1. Installation

Since the latest types of window-mounted ACs are designed to fit most walls and windows, installation is easy. In fact, among the different types of air conditioners, installing a window-type AC is the easiest as there are no ducts to take care of and it comes in a single piece.

The things that you would have to be certain though are the measurements. If your room or house comes with air conditioner holes, make sure to get the measurements so that you can compare its size against the size of the unit you are particularly interested in.

Window-mounted ACs normally come with an installation kit, which should make things easier. However, make sure the size perfectly fits so that there would not be any problems that could even pose danger to you, other members of the household, and the air conditioning unit.

If you plan to have the window-mounted AC installed through a wall opening, it would be just to seek the help of a professional, as this is trickier. There might be the need for a mounting sleeve to make sure that the AC is stable and would not pose a danger to anyone. In addition, it should still be accessible for regular maintenance checks.

  1. Regular Maintenance

All air conditioners do need regular maintenance to make sure they remain capable and energy efficient especially if they are used regularly. Keep in mind that since the outdoor side component is outside the house, it is more susceptible to dirt and all kinds of debris that can accumulate not just on the exterior part of the window-mounted AC but inside the unit as well.

Such dirt and debris accumulation will eventually take its toll on the performance of your window-mounted AC. Experts suggest having ACs cleaned at least once a year and never to wait until you think there is something wrong before making that regular maintenance cleanup and checkup.

Chances are if you wait for something to go wrong before having it checked, then you have to be prepared to shed more money especially compared to what you should have allotted for regular cleaning and checkup.

Choosing Wisely And Going For What Fits Your Needs

Gone are the days when buying a window-mounted air conditioner used to be simple with a quite a few brands and designs to choose from. Today, there are tons of choices the moment you enter an appliance store and more often than not, salespersons will leave you even more confused than the moment before you walked in the store. This is why experts suggest never going inside an appliance store without knowing what you want or at least trimmed down your choices to a few.

As what have always been said over and over again, the only trick in choosing window-mounted AC units wisely is selecting the one that is suited to your room. Do not buy a unit just because it looks good or has a certain feature. Always make sure that the window air conditioning unit has the right BTU, power, and size for the specific room in order for it to function effectively and in order for you not to spend more on electric bills.