Nearly 75% of American homes are fitted with some type of air conditioner. The U.S. Department of Energy estimates air conditioning use makes up 6% of all electricity generated in the country. More than this, the purchase of an AC is a big investment. Furthermore, once you buy an AC, you will have to live with it for a decade or more. This is why you must do your homework when in the market for a home cooling unit.
Basic Factors to Consider Before Buying Air Conditioners
There are a lot of different types of air conditioners available. Before discussing the types, we must consider some basic factors.
Budget is the single most important factor that limits the type of air conditioning unit you will buy. So let us take a look at a budget-wise breakdown of the various types of home air conditioners.
- Portable and window air-conditioners are the most budget-friendly. However, each unit is only capable of cooling individual rooms.
- Mini-split AC (also known as ductless AC) is also only good for cooling one or two rooms. If you choose to use this system to cool your whole house, then it will have to run continuously. This will make it rather costly for daily use and not very effective.
- Smart air-conditioners are available in window type, portable, or mini-split. They are more expensive compared to conventional ones to purchase. However, due to their energy savings, they are cheaper to run daily.
- Central air-conditioning is the most effective of all types mentioned so far. It is also the most costly. It has a longer life compared to portable or window type of ACs, but they also cost significantly more to run.
- By far the most costly option to purchase is the geothermal cooling unit. Their efficiency is unmatched, and over time will recover their own cost with energy-saving. If you have the funds to purchase this, then you will never have to worry about buying another AC. It will pretty much last your whole life.
Understanding Energy Utilization
To understand the energy efficiency of an air-conditioner; there are two terms you need to be familiar with. SEER stands for “Seasonal Energy Efficiency Ratio” and EER is “Energy Efficiency Ratio”. These two figures are a way of measuring how efficient an AC is. Usually, a central air conditioner will have the SEER value while room ACs will have the EER value displayed.
The SEER value is the efficiency of an AC for the whole season. The EER is a standardized value for its efficiency. The greater the SEER value, the better the performance. In 1992 the typical SEER rating was 9, the government raised this and set the minimum at 13. Units available in the market today can go up to a SEER rating of 21. Most people typically purchase ACs with a SEER rating between 14 and 16. The higher the SEER value an AC has, the more expensive it will be.
The cooling capacity of an air-conditioner is measured in British Thermal Units or BTUs. A one-ton air-conditioner is 12000 BTU. So what is a BTU? Well, it is the amount of heat needed to increase the temperature of 1 pound (O.45 Kg) of water by 1° Fahrenheit (0.56° Celsius). In regards to an AC, it is the amount of heat that can be removed in an hour. A 12000 BTU will remove that many units of heat per hour. The higher the BTU numbers the more heat that can be removed.
Typically air-conditioners fall in the following ranges:
- Portable air-conditioners: 8,000 to 12,000 BTU
- Split air-conditioners: 9,000 to 36,000 BTU
- Window air-conditioners: 3,000 to 25,000 BTU
Right Size Matter
Selecting the correct sized AC is important. An undersized unit will not cool the space properly, whereas a large-sized one has several drawbacks.
An oversized air conditioner will have a higher upfront cost.
It will also have more wear & tear. This is because the unit will run and pause more frequently than its design allows. An AC that is too big for a given space will cool it down quickly, after which the compressor will shut down. It will come on again when the temperature rises above the set temperature. This on-again-off-again cycle occurs more frequently with units that are too large for a given space. It causes stress on the system. Which in turn leads to breakdowns and higher upkeep costs.
The compressor of an AC that is too big for a given area will stay shut down most of the time. When this happens, not enough moisture gets removed from the air. This makes the room uncomfortable.
When buying an air conditioner, it’s important to ask the seller how long the warranty period is, whether there is a warranty card, and where the nearest after-sale service dealer is. The more famous the brand, the easier it is to find a service dealer and components for repairs.
No matter what household appliances you buy, you need to consider the noise it generates during use, as excessive noise caused by the air conditioner will affect your sleep and mood. Therefore, it’s best to ask the seller about the noise situation or test the AC before buying it.
Types of Air-Conditioners
This type of system is used to cool the whole house from one location. The cool air is then distributed through a system of ducts and vents located in the different rooms.
This type of system has some advantages. It cools the whole house, thus maintaining a regulated environment throughout. Air is dehumidified naturally. As there is only one unit, minimum maintenance is needed. It is compatible with programmable thermostats.
The problem is that an AC of this size requires a professional installation, hence more expensive.
Your house must have a ducting system. Dust and allergens are spread throughout by the circulating air.
Your energy bills may be higher because you may be cooling rooms that are not being used daily.
This type of AC is made up of two separate parts. It has an outdoor unit that houses a compressor and a condenser. The other is an indoor part with blowers and a thermostat. The indoor part is usually mounted on a wall and has the blowers. Tubing is used to connect the two parts of the AC.
This type of AC is used to cool individual rooms, as they are small units. It can be a costly prospect if you have to install an AC in each room of the house. But it is more energy efficient as people only run the unit installed in rooms they are using. Units in rooms not being used remain turned off. They are also easy to install.
A window-type AC is an all-in-one unit installed in a window or by making a hole in a wall. Again they are suitable for cooling individual rooms and not multiple rooms. A removable filter has to be cleaned regularly. They are easy to install and maintain. As you only cool the space being used, they are cost-effective.
They can, however, be a bit noisy and are an eyesore from the outside. Not all windows will support these units, so there may be rooms in which you can’t install them.
Very similar to window ACs, they are single units with all components housed inside. The difference is that they are placed on the floor and can be moved from room to room. Besides a power outlet, they need a window outlet to remove the exhaust via its funnel. These are great if a window or split is not feasible.
Benefits include the ease of mobility and quick setup. They do not need any permanent installation. They do tend to be noisy when running. As they are smaller units, they cannot cool up large rooms.
A relatively new way of cooling that makes use of the earth’s insulating properties. It is based on the fact that temperature below 4 feet of ground remains a constant 55° F throughout the year. A system of looping pipes with heat-conducting fluid runs between 4 to 6 feet under your house. A heat pump sucks up the hot air from the house and transfers it to the liquid in the pipes. As the fluid circulates in the liquid, it dissipates the heat in the ground and returns cool air into the house.
This system has a long lifespan, is relatively clean compared to other cooling methods, and is very efficient. The drawbacks are that the setup is expensive. Since loops have to be set up underground, the location matters.
Hybrid (Dual Fuel) Air Conditioner
This system uses a gas furnace and an electric-based air-source pump. The system switches from using fossil fuels to electricity depending on the outdoor temperature. When it becomes too cold for the heat pump to work, the furnace automatically starts working. The temperature at which the switch occurs is programmed by you. During summer, the heat pump sucks hot air from indoors and throws it out. During winter, it is the opposite.
The benefits include low utility bills and a carbon footprint. The drawbacks are the high initial cost and long breakeven time.
A smart air conditioner allows you to control the temperature of your house via a smartphone. The ability to download an app and run the AC through Wi-Fi is what makes them smart. The ability to control your AC with even voice commands from anywhere is one of the benefits. Since you control which rooms you want to cool and when smart ACs save energy without compromising comfort. Finally, they leave a much smaller carbon footprint compared to conventional air conditioners. The only issue is they require a bigger investment upfront.