Air Conditioners – An air-conditioning system can provide comfort for occupants by lowering the air temperature and humidity. High humidity levels in a house can produce unwanted moisture damage. There are various other methods of controlling humidity, see Ventilation Section. A properly sized unit is important, an undersized unit may not work well in hot weather and an oversized unit may cycle on and off without running long enough to reduce the humidity.
Air Conditioning systems are sized in tons. A “TON” is a measure of an air conditioner’s ability to cool. One ton is the ability of your air conditioner to cool 12,000 BTUs (British Thermal Unit) in an hour. Likewise, a “2-ton” central air conditioner is able to cool 24,000 BTUs per hour.
Air Conditioners are also rated for Seasonal Energy Efficiency Rating (SEER) and Annual Fuel Utilization Efficiency (AFUE). SEER provides an annual measure of the efficiency of the air conditioner. Higher numbers use less energy. An AFUE is given in a percentage and a higher numbers use less energy. For more information check out our Energy Efficient Products Section. which can help you find the best unit.
For additional information on air conditioning check out the Natural Resources Canada website.
Types of Air Conditioners – There are primarily three different types of Home Air Conditioning systems – Window fixed, mini split ductless room or portable and full house split air conditions systems.
1.Window or Portable A/C – fits inside a window – Good for single room conditioning.
2. Mini Split Ductless – two parts – Condenser typically sits outside and the other part is connected to a wall and provides cooling, good if you have an older house which uses a boiler system and does not have a plenum. Typically this system will cool a single area, depending on how large a unit you buy.
3. Whole House Unit – Most common for houses – two parts – Condenser sits outside and the evaporator which sits inside the Plenum above the furnace – this system connects to the plenum to cool the whole house.
What size of an A/C unit do I need? – To size an air conditioner you must first decide which type (window/portable, mini split, whole house) would best be suited for your specific requirements. Do you need to cool a single room or multiple rooms such as an entire house. Does your house have the distribution system in place such as a duct or plenum system, to distribute the cool air throughout the house. You may be limited to a window or ductless system such as the case with a boiler type heating system in an older house. In some cases you may be able to install a split A/C system in the attic or even retrofit a duct/plenum system utilizing closet space.
Whole house units or split A/C systems – Are rated from 12,000-42,000 or approx 1- 4 ton’s. Sizing an whole house unit is more complicated than a window type unit. Insulation levels, room sizes, ceiling heights, size and orientation of the windows and doors plus other considerations all have an effect on the proper sizing. You should use a licensed HVAC Specialist to assist you.
NOTE: Sometimes some HVAC Sales people will just sell you the exact same size you already own or just rough estimate it. This may not be a good idea. What if you updated your windows and or insulation levels in the house, this house has just become more tightly sealed – your older unit may not be a proper size any longer.Make sure you use a Licensed HVAC Specialist, to make the actual calculations.
Window A/C’s and portable units – are typically rated or advertised in BTU’s (5000-12,000 BTU’s). Your Best Digs is a website which compares 20 portable A/C units, and if you read the article there is a section on how to determine the size (BTU’s) of A/C unit you need for a specific size room…read the whole article it’s very interesting. You can also use the NRCAN Air Conditioning Your Home Guide for much more detailed info and calculation guide…see page 41 Annex A.
A/C – Rebates – You may be eligible for Rebates from Enbridge. Individual manufacturers may even offer an incentive program, make sure you ask your approved retailer. Find out which manufacturer your approved retailer is recommending. Typical brands include Kenmore, Goodman, Lennox, Sears, Keeprite and then check that mfg website to see if they offer any further incentives/rebates directly to YOU the consumer.
A/C – Service/Maintenance Contracts – Often clients ask me about maintenance programs or service contracts. My personal belief is that if you don’t mind paying a small monthly fee you should inquire about a service contract and or a maintenance contract. A contract usually covers parts and labour, read the contract to see which parts are covered. Enercare and Reliance Home Comfort are large HVAC resellers with several types of maintenance contracts. There are many other resellers in Ontario who can help, but there are to many to list here, see the section directly to your right A/C – Where to Buy or Rent. Another good point to consider is that when you sell your house the service contract may be transferable to a new buyer/owner.
A/C – Life Expectancy – Some manufacturers indicate that the typical life expectancy of a A/C Condenser is approx 10-15 years (see Study of Life Expectancy of Home Components page 11) where some may indicate 15-20 years in cooler climates such as Canada (Ontario) where A/C units are not utilized as much. I also find that some people don’t use the A/C often or the summer days in Ontario don’t justify the use of an A/C. It’s not uncommon for me to inspect a house where the A/C Condenser for a full house system is over 25 years old and is still in working condition, although for how long…who knows!.
Today’s appliances – A/C’s and Furnaces have so much more electronics and parts that a part replacement or improvement may be required within 5-10 years again depending on how often they are being utilized…this is where a Service/Maintenance contract is a good idea. You may just need a recharging of the system.
A/C – Buying or Renting – There are many places to shop for A/C units from small specialty HVAC companies to large national resellers to home department stores. If you look around you could find a good deal, just make sure the contractor is licensed. And ask if there are any rebates and if the price quoted includes the rebate. Some resellers will offer to rent A/C units. Renting is a good idea if you don’t have the money to purchase an A/C unit, which could run anywhere from $3000-$6000 depending on size, installation and place you buy it from. Make sure you read the rental contract, you could end up paying a lot more over the contract period and keep in mind if you decide to sell your home, do you have to pay out the contract or can it be transferred, assuming the new home buyer wants to continue paying. Some rentals also cover maintenance and replacement parts for no additional charge – make sure you look for this…read the contract!
A/C – Where to Buy or Rent – Please take the time to thoroughly research the information to help you decide what to buy, how large to buy and most of all who to buy it from. HRAI – Heating, Refrigeration, and Air Conditioning Institute of Canada can help you find a licensed HVAC contractor. Make sure you read over the section on Life Expectancy/Pricing, Contractors and Buyer Beware sections for more info.