Air conditioners remove heat (cooling), remove moisture (dehumidify), and filter the air. It is very important to get the right size air conditioner,
so that it can properly cool and dehumidify, thus making the room comfortable.

If the unit is too big it will cool the space but will not run long enough to properly dehumidify, thus the room will be cool but clammy. If the unit is too large it can also ice up, and will need to be turned off in order to de-ice. If the unit is way way too big, then it can short cycle. Short cycling is where the unit turns on cools a little but is fooled into thinking the entire space is cool. So getting the proper size air conditioner is very important.

A proper sized unit may run for longer time periods, but will remove more humidity, an important function of an air conditioner. For over 20 years we have a tried and true method of sizing air conditioners. We use a slide rule chart. We do not used any basic guides that are printed on any of the boxes. These do not cover enough of the many elements that need to be considered, including:

• the square footage of the room,
• what type of room,
• sun exposure,
• what story of the house,
• how many people in the room,
• and other factors.

A large room will need more cooling as there is more heat in it. Measure the length and width of the room. Having accurate dimensions will result in proper sizing of the unit.

A northerly facing room gets virtually no sun is the easiest to cool. A southwesterly facing room that gets sun throughout the afternoon is hard to cool. An easterly facing room that only gets the morning sun would fall in the middle. But a southwesterly room could have a good amount of shade and be no harder to cool than the northerly faing room.

An attic space will often get brutally hot and thus is hard to cool, as that's where the heat collects as the heat rises through the house. The basement will be the easiest to cool, followed by the first floor, then the second story, with the attic being the hardest to cool. We see this difficulty in cooling the room over the garage as well, as it is essentially an attic type space with no ar space above it to collect the heat.

Most guides assume 2 adults in the room. If you add more people, then you add more heat, and need more cooling power. Add large pets, and you will also add to the amount of heat that needs to be removed. Add computers, TV's, and other things that produce heat, and still more cooling is needed.

Primary cooling space vs. Multiple rooms

A Living room and dining room with a 10 foot wide opening between them can be cooled as on one room, as the air will flow through an opening of that size. Air normally does not travel thru normal doorways well. If you want to cool 2 bedrooms that are separated by a hallway, getting one air conditioner for Each room is going to be a better application than trying to do it with one air conditioner. If you try to do two bedrooms with one air conditioner, you very well might not properly cool the primary room, you might run into the unit icing up, you might not properly dehumidify.

Mobile homes that get a lot of sun are very difficult to cool. Appliances, Computers, and other equipment need to be considered. Anything that Adds heat, produces heat, or creates a cooling loss, needs to be considered.

Electronic controls are found on many models today. These allow for setting the desired tempurature digitally. These will often include on/off delay timers. Electronic models will often have a remote control. Models have between one and 4 fan speeds to allow choice between noise and air flow. Some have exhaust vents that will open for fresh air, and close for maximum cooling, Some models come with a slideout chassis so the unit can be easily installed, first mounting the lightweight shell, then sliding the main chassis into the sleeve. Some slide out chassis models can be used as either window models or through the wall.

EER Energy Efficiency Rating shows the number of btu's of heat removed for each watt of electricity. A higher is number usually better, but some of the higher EER units have sacrificed dehumidification to achieve that high EER. We strive to properly size air conditioners for our customers. We look forward to helping you find the best air conditioner to keep you cool and comfortable.

Most air conditioners operate on 115 volts. Most come with the expandable panels to fit in your window. 5,000 to 15,000 btu units can run on 115 volts. 5,000 is a typical bedroom air conditioner, while 10,000 to 12,000 is more often for a living room or family room.

230 volt air conditioners require a special dedicated electrical outlet. Although some units can be 10,000 btu's and less and run on 230 volts, most 230 volt units are very large, often only used in larger spaces such as found in businesses. Commonly they are 18,000 to 36,000 btu's. 18,000 btu and larger air conditioners can still be mounted into windows, although they can be mounted through the wall in some applications.

There are air conditioners that are specially designed to fit into sliding or casement windows. Windows that slide sideways to open can fit these easily. Casement windows that open sideways, can fit these as well depending on the width. Common crank out windows are about 15 inches wide and will accomodate these units. Crank out windows that are larger, such as 20 inches wide, make for a very difficult installation.

Most casement air conditioners are about 14 1/2 inches wide, and about 20 inches tall. The expander is vertical unlike most air conditioners that expand horizontally. The maximum height with the expander is often close to 40 inches.

Portable air conditioners are great for applications that provide no other options. However if you are considering chosing a portable unit, when you could use a regular window unit, there are a few things you should know.

• They still need to be sized properly.
• They must be vented outdoors
• They are louder than window units, as all of the unit is inside the room.
• Some models require you to empty a bucket regularly. This is where the humidity goes when it removed from the air.
• They are more expensive than typical window units.
• To properly cool a room, it takes a few hours, so moving it from one room to another on a hot day does not always allow for adequate cooling.

However if your application leaves no other option, portable air conditioners can provide a comfortable room.

Through the Wall air conditioners are normally fairly standard in dimensions. The air conditioner and the sleeve are purchased separately. The sleeve is mounted through the wall, and then the air conditioner is mounted into it. GE has maintained standard sleeve sizes for many years, so if you needed to replace one, you would not need to do any carpentry work, just slide the old one out, and the new one in. Frigidaire has offered collars with some of their wall units, so that thier unit will fit inside other brands old sleeves.

You will pay more more a wall unit that a window unit of the same size but thier ability to be replaced easily is one advantage of the true wall units. Also wall units tend to all of the air exchange through the back, so that they can fit into much thicker walls, sometimes over 12" thick.

Some window units have slide out chasis so that they may be installed through a wall. Most window units breathe through the back, but also the top and sides which limits how thick of a wall they can be installed into. They also are very non standard in dimensionally in height and width, so when it is time to replace it, you may need to do carpentry work. However these slide out chasis units are often less expensive than true wall units.