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Personal: Residential

Cooling and Ventilation Equipment –
Air Conditioners

Introduction and Types

When you're in the market for new cooling products, it pays to learn all you can about them first. With the proper facts in hand, you can make choices that will save you money and help protect the environment.

The EnerGuide rating and ENERGY STAR® symbol can help you identify the most energy-efficient products available in Canada.

In summer, high relative humidity, elevated air temperatures and bright sunshine can combine to produce an uncomfortable indoor environment. Air conditioning can provide comfort for occupants by lowering both the air temperature and the humidity level in the home.

There are three main options available:

Central air conditioners cool only while and heat pumps also provide heat in winter. Central air conditioners and heat pumps are used to cool an entire living area. Central air conditioners cool only while heat pumps also provide heat in winter. Room air conditioners can effectively cool up to three rooms at low cost, and can be installed with minimum effort.

Before you decide what to buy, ask yourself if the whole house must be air-conditioned or if your needs would be satisfied by cooling one or two rooms. The answer will determine which type of air conditioner would be more appropriate.

While your basic choice will be between central air conditioners and room air conditioners, there are several different kinds within each type. The most common are listed here, but there are other designs and larger sizes.

Central Air Conditioner Types

Single-package unit

A single-package unit contains all the components and generally mounts through the wall or on the roof. Ducting to and from the unit conveys air to and from the rooms. This type is not commonly used in residential applications.

Split-system unit

A split-system unit consists of indoor and outdoor sections. The indoor heat exchanger, or coil, mounts above the furnace, inside the ducting. The outdoor section contains the remaining components, and the two sections are joined by refrigerant lines connecting the indoor coil to the refrigeration components in the outdoor section.

Mini-split and multi-split units

Mini-split and multi-split units are split systems but contain more than one indoor coil connected to one outdoor unit. They have many indoor units. Because they do not require ductwork, they are ideal for new additions to homes. The indoor section simply mounts on an inside wall, the ceiling or the floor. The outdoor and indoor units generally have a very slim profile compared to conventional split-systems.

Small-duct high-velocity units

Small-duct high-velocity units are central air conditioners distribute air through plastic pipes in partition walls to outlets and inlets. These units can be retrofitted in homes with electric or hydronic baseboard heating that have no ductwork.

Central Air Conditioners – Purchasing Considerations

Heat Pumps

If you have an electric or oil furnace or a conventional gas furnace and your space heating costs $1,000 or more per year, you should consider installing an efficient air-source or ground-source heat pump instead of a central air conditioner. Ask two or three contractors how much more it would cost to add a heat pump to your furnace. Heat pump SEER ratings are competitive with those of central air conditioners, but heat pumps have the added advantage of providing savings in heating costs during the winter.

Heat pump savings range from a low of about 20 percent where gas is the primary heat source to as high as 60 percent where an electric furnace is the main source of heating. If the additional capital cost divided by the estimated savings is five years or less, consider installing a heat pump instead. They are good for the environment and are an efficient way of using electricity for home heating.

More information on heat pumps

Room Air Conditioner Types

Through-the-wall (TTW) units

Some room air conditioners are designed to fit through the wall. These units, also referred to as "without louvered sides," are built this way because the wall framing would interfere with the airflow through the sidewalls of the air conditioner. These air conditioners tend to be less efficient than regular window units. They must also meet minimum efficiency regulations. Work is under way to include TTW units in the ENERGY STAR specifications.

Although not common in colder climates, some room air conditioners are built to provide some heating, either with electric resistance heating or by what is called a reverse cycle. Reverse cycle means that the room air conditioner can act like a heat pump and heat the room. When the flow of refrigerant is reversed, heat is released inside.

Window-mounted units

The majority of room air conditioners are the window-mounted, louvered type. They are mounted into an open window and plugged in. As the size increases, the amount of electricity required increases and the customer may have to install a dedicated electrical circuit, or a 240-volt circuit for the larger sizes.

The EnerGuide label describes window-mounted units as louvered – that is, with exterior side vents. This permits better air exchange, which is in part why the minimum regulatory and ENERGY STAR required performance levels are higher for window-mounted units than for TTW units that are non-louvered (without louvered sides).

Window-mounted types are available for installation in single- and double-hung windows, as well as for horizontal sliding windows and casement windows.

Portable units

Portable room air conditioners have a hose that is used to exhaust heat to the outside. Because they are on wheels, they can be moved from room to room. Water condensed from the cooled air has to be removed and drained away through temporary ducting to the outdoors. There is currently no CSA Standard or energy efficiency rating for this product.

Room Air Conditioners – Purchasing Considerations