In general, there are four types of central air conditioning: Split systems are the most common type of central air conditioner found in the U.S. Inside the house, tucked in a cabinet, is the evaporator coil, which removes heat and moisture from the air. Outside the house, a metal case contains the condenser coil, which releases the heat, and the compressor, which pumps refrigerant between the two coils. The indoor component of the air conditioner is connected to a network of ducts, and a blower circulates the cold air through them to reach all parts of the house. This type of system is the most economical to install in a house with a central furnace, because it can share the ductwork used by the heating system. All of the central air conditioner systems in this report are split systems. Heat pumps are a variation of the traditional split system. During hot summer months, it pumps heat from the house and releases it outside. In the wintertime, it extracts heat from the outdoor air and uses it to warm the house.

Because of that, heat pumps can be used effectively for both heating and cooling in mild climates. However, heat pumps do not generally work well when temperatures stay below freezing for a long time, so they are not the best choice for cold climates. A specialized type of heat pump, called a ground-source or geothermal heat pump, could be an option for colder environments. It works by drawing heat out of the ground rather than the air. -- and not every contractor is familiar with or capable of doing the installation.how much does it cost to service ac unit Packaged central air conditioners combine the evaporator, condenser and compressor in a single unit. what is the best rated hvac unitThe air conditioner is usually placed on a roof or a concrete slab near the foundation. ac units on the wall

Ducts running through the exterior wall or roof draw air from inside the house and return cooled air indoors. This type of air conditioner can also be used in small commercial buildings. When combined with a set of heating coils or a natural gas furnace, it eliminates the need for a separate furnace inside the building. Ductless mini-split systems can be a good choice for houses that do not have ductwork. Like a basic split system, the ductless mini-split combines an outdoor compressor and condenser with one or more indoor air-handling units. These units are mounted high on the wall and have blowers attached. Tubing connects the indoor and outdoor units and circulates refrigerant between them. Each indoor unit is installed in a separate room and cools that room only, much like a window air conditioner. The main advantage of ductless mini-split systems is that they can be installed without tearing up walls to install ductwork. They also allow the flow of cold air to be controlled independently in each room (or shut off altogether in empty rooms).

If used to cool an entire house, mini-split systems are more expensive than ducted central air conditioning systems, costing roughly 30 percent more for the same amount of cooling power. However, they are also more efficient, since they avoid the energy loss associated with ductwork. When comparing central air conditioners, one term you'll see repeatedly is the seasonal energy efficiency ratio (SEER), a measure of how much energy the air conditioner uses to cool a home. Central air conditioners range from 13 to 28 SEER. The SEER is calculated by taking the total cooling output over the course of a summer, measured in British thermal units (BTUs), and dividing it by the total amount of energy the air conditioner uses over that same period. These figures are based on a theoretical average climate for the United States. In reality, of course, the same air conditioner's performance may vary considerably based on how hot and humid it is outdoors. SmarterHouse, a project of the American Council for an Energy-Efficient Economy (ACEEE), recommends that people who live in hot and humid climates choose an air conditioner with a SEER of at least 15.

They also note that if you have an older system with a SEER of 10, upgrading to a model with a SEER of 15 could cut your air-conditioner energy costs by a third. Another measure of air conditioner efficiency is the energy efficiency ratio (EER). This measures the air conditioner's efficiency at any given moment. It's simply the cooling capacity of the air conditioner, as measured in BTU per hour, divided by its energy consumption in watts. Energy Star ratings for central air conditioners are based on both SEER and EER. To qualify for the label, a standard split-system central air conditioner must have a SEER of at least 14.5 and an EER of at least 12. For single-package units, the requirements are lower: 14 SEER and 11 EER. The Energy Star label is only one award a central air conditioner can earn for efficiency. The Consortium for Energy Efficiency (CEE) goes beyond the Energy Star ratings by defining three additional tiers for super-efficient models. A CEE Tier 0 unit is one that meets the Energy Star criteria.

Tier 1 split central air conditioners have a minimum of 15 SEER and 12.5 EER, Tier 2 air conditioners have a minimum of 16 SEER and 13 EER, while the Tier 3 specification is a minimum of 18 SEER and 13 EER. State and local governments, as well as utility companies, may offer rebates for choosing a central air conditioner that meets one of these higher standards, so check those to get the best bang for your buck when buying a new central air-conditioner system.Choosing the right heating and cooling system for your home or property can be a dilemma, with so many available choices and price ranges. This comparison guide lists the pros and cons of each system type, along with a current estimated cost for each style. Please note that costs for each system type vary by manufacturer, and the size of the unit needed depends on several factors along with square footage such as area layout, proper insulation, and no leakage around doors and windows. HVAC Air Conditioning and Heating System

A standard HVAC heating and cooling system is cost effective and convenient, but it also has some drawbacks to alternative systems. Pros of HVAC Units: HVAC systems provide overall cooling and heating to every room that is equipped with a vent connected to a network of ductwork. Systems will cycle on and off as the interior temperature needs to be adjusted. The standard for sizing is 1 ton per for every 500 square feet. For a 2,400 square foot property, you would need a minimum of a 5-ton unit. For an HVAC system for a 2,400 square foot area in Los Angeles, California, the low cost is approximately $3,904.56 and the high end is $4,825.80. This is for a 3-ton unit with a Seasonal Energy Efficient Rating of 18. Cons of HVAC Units: Ductwork can be expensive and prone to leaking when damaged or due to deterioration from age. If you’re having a new system installed to replace or upgrade a current system, the ductwork may need to be updated or modified as well, to ensure it is compliant with the new system.

For a new installation, you must factor in the cost of the ductwork and labor. Unlike a ductless system, you cannot individually adjust the temperature for each room. Window Unit Air Conditioning System Whether they’re installed in a window or a wall, this unit has been heating and cooling homes and businesses for many years, and with today’s technology, they have improved in energy efficiency. Pros of Window Units: Window units come in a variety of sizes from 5,000 BTUs to 36,000 BTUs and are available for cooling only or for heating and cooling. These units are affordable, with current prices ranging from less than $400 to approximately $1,500. Window units are relatively easy to install—simply place in an appropriate window and provide support. Cons of Window Units: Since the unit is installed in either a window or in the wall, it is not as versatile as a portable unit. Because the unit does not have a duct system with vents to every room, the immediate and surrounding area will feel the effects of the cooling sooner, while outlying areas will take more time to condition.

A 12,000 BTU window unit is estimated to cover between 450 and 550 square feet. For a 2,400 square foot area, at least two 18,000 BTU units (18,000 BTUs covers up to 1,000 feet) are needed or one 28,000 BTU unit, which covers 2,200 square feet plus an additional 10,000 BTU unit to cover the remaining 450 square feet. Portable Air Conditioning System Portable air conditioners are an option known for their versatility. Here are a few things to consider when doing comparison shopping. Pros of Portable AC Units: The beauty of portable units is the ability to move them whenever and wherever you like. By removing the drainage tube and window kit used to vent the hot air, the system is easily moved because it’s equipped with casters. Units are affordable, with prices ranging from less than $500 to $1,200. Portables are available in 8,000, 10,000, 12,000, 14,000 and 16,000 BTUs. Systems are available for cooling only, or for heating and cooling. Cons of Portable AC Units:

Homes or offices with carpet may find it difficult to roll the unit. A 12,000 BTU covers an area of 400 square feet. Six units are necessary to accommodate a 2,400 square foot area. Portables tend to have a lower Energy Efficiency Rating (EER). Ductless or Mini-Split Air Conditioning and Heating System Mini-split ductless systems are a newer option in heating and cooling. The unit is comprised of an external compressor/heat pump and internal inverter boxes that connect to the compressor. The boxes can be wall, floor, or ceiling mounted. Lines are run from the inverter box to the compressor; one copper for refrigerant, electric wiring and tubing for drainage and condensation. Pros of Ductless AC Units: Mini-splits are ductless systems, which save money on the installation of a network of ductwork throughout the ceiling. A slim duct line ductless system is also an option, which uses minimal ductwork. Each inverter box is individually regulated with a remote, meaning you can turn off units in rooms not needing heating or cooling.

Systems can be ordered with 1 to 8 inverter boxes depending on your needs. Systems use 208-230 voltage. Ductless systems come with a high Seasonal Energy Efficiency Rating (SEER) and Heating Seasonal Performance Factor (HSPF) that measures the efficiency of the heat pump. Cons of Ductless AC Units: Systems are available with 12,000, 18,000, 24,000, 30,000, 36,000, 42,000 and 48,000 BTUs. A Multi-Zone (5 boxes) with 36,000 BTUs is estimated to cover 2,000 square feet. For homes or businesses with more square footage of 2,400 square feet, the addition of a single 12,000 BTU system with an inverter box may be necessary. Ductless systems are available from many manufacturers. Depending on the size needed, units can range in price for $650 to $6,500 at current prices. Units must be professionally installed due to wiring and refrigerant requirements. What’s your preferred type of AC unit? Do you have an experience with one type over another? Tell us about it in the comments below!