Air conditioning units should be installed by a contractor who is experienced with this type of work. Depending on existing ducts and the type of unit purchased, the price may vary greatly. Get several estimates from qualified contractors before deciding on the unit and installer. Ensure the contractor has experience and works well with you. Get references and check them thoroughly.

that the contractor and any sub-contractors have liability insurance. You may wish to ask who the policy is with and follow up to verify if it is current. They should also be able to produce a certificate of good standing from the provincial Workers' Compensation Board

The efficiency rating is required to be on all air conditioners. Compare units carefully to determine the cost for each type of efficiency. The more efficient a unit is, the more money you will save on energy bills. A more efficient air conditioner will take less energy to run and cool the entire house.

Contact neighbours, friends, relatives and co-workers for opinions on work done recently by a contractor. Or use the business directory for your area or newspaper, radio and television ads to identify contractors. Either way, be sure to check whether the contractor has appropriately certified personnel on staff (licensed air conditioning mechanics, electricians, gas fitters, oil burner technicians, etc.), whether they offer 24 hour emergency service, and what maintenance and service agreements are available for long term care

You will need to determine the appropriate size of the unit needed for your house. This is an important step because units that are too small will have to work harder to cool the home. Units that are too large are simply wasteful and unnecessary. A qualified air conditioner contractor will be able to analyze the size of your home and make recommendations on the size needed

Always get a contract before starting work with any contractor. Make sure all the costs are clearly spelled out. This should include both the cost of the unit and installation. It should also detail payment policies and warranties. Warranties generally cover the compressor and additional parts. Do not choose a unit that has anything less than a five year warranty on the compressor, but a ten year warranty is better. Additional parts may be warranted anywhere from one to five years and are usually separate