As Ontarians, we live for summer and the joys it brings — warm weather, fresh air, camping, barbeques, and more. But nothing dampens the summer spirit faster than a broken air conditioner during a hot, humid day.

Replacing an air conditioner is a big decision for a homeowner. So when something goes wrong with your AC unit, we know how fast you need to collect accurate, unbiased information about your AC repair or replacement options. That’s why we’ve pulled together this air conditioner buying guide to help you navigate every step in the journey.

In this guide, you’ll learn about:

Air Conditioner Basics

In the following section, we discuss the common subjects and terms you will encounter while researching and purchasing an air conditioner, when to replace your AC unit, what size air conditioner you need, and efficiency ratings.

How an Air Conditioner Works

Air conditioners draw in warm air from the home and passes it over an evaporator coil that absorbs heat and removes humidity, which cools the air. The AC unit then expels the heat outside and pushes the cold air back into the room to make the temperature more comfortable.

A diagram showing how an air conditioner works to remove warm air from a home. The air conditioner diagram discusses the evaporator coil, compressor, condenser fan, and expansion valve

To achieve this procedure, most air conditioners contain the following parts:

  • Condenser coil
  • Compressor
  • Metering Device, such as an expansion valve
  • Condenser Fan
  • Blower
  • Electrical components
  • Evaporator coil or “A” coil
  • Furnace or Air Handler (central air conditioners only)

If any of these parts break or work inefficiently, your AC unit may need repairs or replacement.

When to Replace Your Air Conditioner

  • Your AC equipment is 15+ years old
  • After turning on your AC unit, it takes too long for your house to cool down
  • Any part of the air conditioning system is loud or making unusual noises, like bangs, squeaks and scrapes
  • You’ve had previous equipment breakdowns

Later in the guide, we’ll dive deeper into AC maintenance, repairs and replacement. Skip ahead to that section if you want to learn more diagnostic tips. And if you want a more in-depth explanation about how each type of air conditioner works, visit the types of air conditioners section.

Air Conditioner Efficiency and SEER Ratings

Among the most important decisions you’ll make when buying a new AC unit is how efficient you want the equipment to be, a factor known as SEER.

Seasonal Energy Efficiency Ratio (SEER) measures how efficient your air conditioning equipment is, similar to the kilometers-per-litre rating in a car. The greater the system’s SEER rating, the more energy-efficient the AC unit is and the more comfort you will get from each energy dollar.

You may also see air conditioners rated with EER (Energy Efficiency Ratio), which is similar to SEER, but calculated using a steady outside temperature of 35℃ (95℉). In comparison, SEER is calculated using outside temperatures that range from 18℃ (65℉) to 40℃ (104℉).

How to Determine Air Conditioner Efficiency

Ideally, you want to buy the most energy-efficient air conditioner that you can afford. But higher SEER models typically cost more money, so you may want to calculate the annual electricity cost for an air conditioner to see if the payoff meets your needs. If you have an HVAC Energy Management Consultant evaluate your home, they’ll do these calculations for you.

To start, you’ll need to identify four factors.

  1. The BTU output of your chosen air conditioner

    British Thermal Units (BTUs) measures the rate of heat transfer needed to raise the temperature of one pound of water by one degree Fahrenheit or freeze one short ton (907 kg; 2,000 lb) of water into ice in 24 hours. The AC unit specifications will tell you its BTU output.

  2. The unit size (in tons)

    AC units are sized by tons, which instead of weight, describes the rate of heat transfer that results in the freezing or melting of 1 short ton of pure water at 0 °C (32 °F) in 24 hours. 1 ton of cooling is equivalent to 12,000 BTU.

  3. An estimate of how many hours you have the AC unit turned on each year
  4. How much your electricity costs per kilowatt-hour

After you have this information, use the following formula to calculate how much money running an AC unit will cost you each year:

Unit size × BTU/h × operational hours per year × $/kWh ÷ SEER ÷ 1000W/kW = annual energy cost

Let’s break the formula down so it’s easier to understand. A house in Ontario has a central air conditioner with a cooling capacity of 5 tons and a SEER rating of 20. The unit operates 100 days each year for 8 hours per day. The cost for electricity is $0.10 per kilowatt-hour.

The first step is to convert the unit’s size (tons) to BTU-per hour. For reference: A one-ton AC unit is rated for 12,000 BTU-per hour.

(5 tons) × (12,000 BTU/h/ton) = 60,000 BTU/h.

The next step is to determine how much you pay in kilowatt-per-hours compared to the unit efficiency rating.

(60,000 Btu/h) × (800 h/year) × ($0.10/kWh) ÷ (20 SEER rating) ÷ (1000 W/kW) = $240/year

This energy-to-cost rating helps determine what size of AC unit you should buy. The average Ontario home will range from 1.5 to 2.5 tons with a SEER of 13-16.

How to Determine the Right Air Conditioner Size for Your Home

There are nearly a dozen factors that go into choosing the right size AC unit for your home, including the size and age of your home, air flow, how many windows you have, insulation, and how much sun your house gets. We encourage you to consult with an HVAC expert during your shopping process to make sure you don’t miss any factors.

However, you can do rough estimates on your own to help narrow what types of AC units are the best for your needs.

As we talk about in our blog post, How Do I Know What Size Air Conditioner I Need?, home air conditioners generally start at 1.5 tons and go up in half-ton increments.

A one-ton AC unit can cover roughly 750-1000 square feet. So if you have a 2,000 square foot home, you might be looking at a 2.0 – 2.5-ton unit. It’s unlikely any residential home will need more than a 5-ton unit.

You should also consider duct sizing, which is key to ensuring there is adequate air flow for the requirements of the air conditioning system. New units may require more air flow and sometimes the duct work that exists is not set up for the new units.

If you want an accurate size and unit recommendation, you can also schedule a free AC unit consultation with Enercare’s HVAC experts.

How Much Does an Air Conditioner Cost?

The average price of a new, high-efficiency air conditioner ranges from $3,000-$6,000 and includes standard installation from a fully-insured, licensed company, with at least a one year warranty, and all required licenses for installation.

For a more narrow scope, there are five factors that determine the cost of a new AC unit:

  • Air conditioner type: central, ductless, window, wall-mounted, or portable
  • Environmental choices: energy efficiency, sound output, air filtration options (which depend on allergies or other sensitivities), and comfort-enhancing options
  • Personal choices: extended warranties, maintenance plans, and service guarantees
  • Technical requirement: the size of your home, floor plan, number of stories, existing ductwork, and BTU load
  • Code requirements: safety, licensing, and building code requirements

The following table breaks down the average costs for new air conditioners in Ontario.

Air Conditioner Type Average Cost (Including Installation) Average Unit Lifespan
Central Air Conditioner $3,500-$6,000 15 years
Ductless Air Conditioner $3,000-$6,000 20 years
Window Air Conditioner $200-$1,000 8-10 years
Wall-Mounted Air Conditioner $450-$700 10 years
Portable Air Conditioner $250-$700 5-10 years

If you want to avoid the upfront costs of buying and installing an AC unit, then air conditioner rental is an alternative to consider. Our HVAC rental solution is the Enercare Advantage program, which offers you zero up-front costs, affordable monthly payments, and free bi-annual maintenance and repairs by our licensed technicians. If you're ready to schedule a free in-home assessment, fill out our form and we'll be in touch soon.

Renting vs Buying a Furnace or Air Conditioner

The Types of Home Air Conditioners

The type of air conditioner that’s best for your home depends on your cooling needs and price range. The following section discusses the five types of air conditioners that are common in Canada.

Air Conditioner Maintenance and Repair Basics

A broken, underperforming or malfunctioning home cooling system in the peak heat of summer is frustrating. Before you call a service technician about your unit, there are several basic maintenance and diagnostic steps you can perform.

For general AC maintenance and troubleshooting, read our blog post Easy Troubleshooting for Common AC Problems. If you want advice on specific problems, the following section is for you.

Before we dive in, important to note that fiddling with an air conditioner or furnace is dangerous, so we strongly encourage you to consult a licensed HVAC technician for any maintenance work you’re not comfortable with or are unsure about.

Common Problems with Air Conditioners

Knowing what’s wrong with your air conditioner is half the battle. If you notice any of the following issues, your unit likely needs to be repaired or replaced.

Old Age

The average central air conditioner lasts about 15 years. If your unit is showing signs of old age, like poor performance or unusual noises, it’s likely time for a replacement.

Frozen Coils

If your evaporator coils don't get adequate airflow or they are clogged they can freeze and your AC unit may stop working. Dirt and other types of debris can clog the air filters and ducts, which restricts warm air from reaching the coils. Without the warm air, the coils can’t cool the air being pushed through your AC unit efficiently and may eventually freeze.

If your coils are frozen, you may notice:

  • Warm air coming out of the vents, despite the AC unit being on
  • Condensation or ice on the AC unit or the outdoor refrigerant line
  • Obvious signs of ice on the coil after opening the air handler

If you discover a frozen coil, don’t try to clear the ice by hand because you may damage the unit. Instead, you can use a do-it-yourself remedy to thaw the ice before consulting with an HVAC technician. If the following steps don’t resolve your problem, we suggest you contact an AC expert. You may have a more serious malfunction, like a refrigerant leak, which must be handled by a licensed professional.

  1. Turn off the AC system using the external (wall) thermostat and make sure to turn off the unit using the furnace switch.
  2. Replace any dirty air filters.
  3. Open the furnace or air handler’s panel.
  4. Let the ice thaw naturally. Having the fan run can cause damage to the blower motor and the circuit board.
  5. After the coil has thawed (this may take 24 hours or more depending on how much ice buildup there is), reseal your unit.
  6. Turn on the power by turning on the furnace switch and adjusting the thermostat to come on and wait for your home to cool. If the home reaches the desired temperature and the AC unit turns off, you’ve probably solved the problem. If this doesn’t happen, consult an HVAC technician.

Refrigerant Leak

Refrigerant is the chemical found within the coils that helps cool the air, and without it your air conditioner won’t work. Refrigerant exposure can be dangerous, so if you have a leak (or suspect one) it’s crucial to contact an expert.

If you have a refrigerant leak you may notice:

  • A loss in cooling power
  • Air vents not blowing cold air
  • Hissing sounds coming from your AC unit
  • Frozen evaporator or condenser coils
  • Unusually high AC-related electric bills

Overworked Capacitors and Contactors
If your AC unit isn’t blowing air, you may have a capacitor or contractor issue. Capacitors and contactors work to keep essential motors running in the unit, such as the fan motor and blower motor. The parts require a significant amount of electricity to run, so they tend to get overheated and overworked during hot summer months — especially on older AC units.

Defective Thermostat

Sometimes the unit is not working due to other parts of the HVAC system, like a faulty thermostat. If the thermostat is not working properly, it may give the AC unit wrong information, which causes it to run when it shouldn’t or not turn on when it should.

If you want to read more AC troubleshooting insights then check out our blog post, What You Need to Know About Air Conditioning Replacement.

Have any questions?

We hope this air conditioner buyer’s guide helps make your purchase decision easier. If you have any additional questions about what type of home cooling solution best fits your needs, please feel free to get in touch with our sales team.

You can reach our sales team at 1-855-255-5458 or fill out the following form to request a free in-home assessment and price quote.

If you have any quick questions but don’t want to call us, you can also reach out to us on Facebook or Twitter.

Get a New Air Conditioner with Enercare

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