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Personal: Residential


When you’re in the market for new heating 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. The items in the list on this page will direct you to further information about specific areas related to each subject.

Buying a Forced-air Furnace

You cannot shop for a furnace the same way you shop or a camera or a pair of shoes. There are no “furnace stores” that allow you to examine, compare and price different makes and models.

As you consider a particular type of furnace, read the literature carefully to find out if it describes the features you are looking for. To compare the efficiency ratings of various models, look for the EnerGuide rating.. This will show you the annual fuel utilization efficiency (AFUE) rating, not just the steady-state efficiency. Make sure to distinguish the two types of ratings. Ask for an ENERGY STAR qualified model to ensure you are offered a high efficiency furnace.

Our Table can help you compare the ratings of several models. Review our on-line list of models to compare ENERGY STAR qualified and non-ENERGY STAR equipment.

But there are still ways to get first-hand information on the makes and models available, and their relative costs:

  • Contact a number of heating firms.
    Ask them for the manufacturers' illustrated sales literature on the furnaces they sell and install.

  • Check the references of the contractor.
    It is important to hire a contractor who will install your equipment properly so that it will operate efficiently. The Better Business Bureau will know contractors who are members and can tell you whether any recent complaints have been filed against them. Your local Chamber of Commerce or Board of Trade may also be able to provide information.

    If your neighbours have had similar work done recently, ask them how satisfied they were with their contractor. If you are buying a relatively new type of furnace design, try to get the names of other homeowners who have had such equipment installed, and find out what they have to say about the appliance’s performance and the work of the installer.

  • Contact local utility companies, fuel dealers and provincial/territorial heating fuel regulatory agencies.
    Local utilities and fuel suppliers can often provide information on the cost of purchasing, renting and installing furnaces and the estimated seasonal heating costs of the type of equipment you plan to use. Local utility companies, fuel dealers and provincial/territorial heating fuel regulatory offices sometimes keep lists of fully qualified registered or licensed contractors.

The Home Energy Audit

Before replacing your heating system, you should consider having a home energy audit carried out by a qualified EnerGuide for Houses advisor. The advisor will provide you with a thorough whole-house energy evaluation and analysis, including:

  • a guided tour of your house to point out areas of air leakage
  • an easy-to-understand report on your home's energy performance
  • a home improvement plan that will show you how to lower your energy costs
  • an EnerGuide for Houses rating and label, so you can compare your home with others across Canada

By following up on the recommendations of such an audit, you may be able to reduce the size of furnace required.

What a Contractor Can Do

A heating contractor cannot determine what size of heating system you need just by walking through your house. The "size" of heating system represents its heat output when it is running in steady-state operation. If you are replacing an existing heating system, the output of that system will give only a rough idea of the maximum size you should consider. The contractor will have to calculate the heating requirement of your house very carefully, first by factoring out other usage, such as for the water heater and kitchen range. The calculation will be based on one of the following:

  • the fuel consumption of your present heating system over a known winter period, and the climatic history for your location over that same period
  • a thorough measurement and examination of your house to determine size, insulation levels and degree of tightness of the building envelope

To make sure your new heating system is the proper size, the quotation and contract should include a statement like the following: “The heating equipment size will be determined by a heat loss calculation using the formulas published by _______________________ ”(a recognized organizations such as a electrical utility, the Canadian Oil Heat Association, the Canadian Gas Association (CGA), the Heating, Refrigerating and Air Conditioning Institute of Canada (HRAI), or the Canadian Standards Association (CSA). A copy of these calculations will be given to the homeowner.

To determine the size of your new furnace, ask the contractor to provide you with the calculation results, including a summary of the general design assumptions and a statement of the calculation methods used. A calculation based simply on the floor area of the home, or replacing the furnace with one of "equivalent" size, is not adequate in most cases. If the contractor does not show any interest in either a detailed assessment of the house or a review of your past heating bills, then the calculation of your furnace size is likely to be no better than a guess.

Even the best furnaces do not run at maximum efficiency if they are oversized. Use your present furnace to gauge the size of a replacement, and you could end up with a unit that is as much as three times too large. You will pay too much, and your ductwork is likely to be undersized for today’s energy-efficient equipment. Your home might even feel uncomfortable. An improperly sized furnace will not be as efficient as a furnace tailored to your specific heating needs.

What the Written Estimate Should Include

Before you decide what to buy, obtain firm, written quotes/estimates on:

  • The cost of upgrading your existing equipment
  • The cost of buying and installing a complete new unit
  • he cost or renting heating equipment or leasing to purchase

An itemized list should spell out all material and labour costs in the bid including:

  • Alteration or improvement of existing heat distribution ducts
  • Installation of furnace and fuel supply piping and ductwork
  • Installation of water heater and vent
  • Installation of chimney liner and any related masonry work
  • Installation of additional equipment, such as gas appliances, humidifiers, air cleaners or air conditioners
  • A statement describing how much existing equipment will be used in the new system
  • A rough diagram showing the layout of new wiring, ductwork or water pipes and the location of supply piping and heating equipment
  • A statement that clearly defines who is responsible for:
    • all necessary permits and payment of related fees
    • on-site inspections by the utility
    • scheduling of all other required work by the utility, such as: Supply pipe installation and hook-up or alterations to the transformer or related outside equipment
    • removal of existing equipment that will not be used with the new system
    • all related costs, such as subcontracts with trades people
  • A clear estimate of when the work will be completed
  • A warranty for materials and labour
  • A schedule and method of payment
  • A statement that indicates when electric service will be interrupted and for how long

Additional electrical space-heating equipment costs:

  • Alteration or replacement of the main service panel and service entrance
  • Alterations to service wires above or below grade to the transformer pole
  • Transformer pole replacement (sometimes the responsibility of the customer in rural areas)

Get several estimates on the work to be done. Some contractors may be better at explaining what has to be done. Some may use higher quality components, and others may schedule the work at your convenience.

With these figures and a reasonable estimate of the probable annual fuel savings, you will be able to determine how long it will take to recover the cost. This is not the only factor to consider, but it is certainly important.

If you are installing additional gas-fired appliances at the same time, the contractor installing the heating system may be able to combine the two jobs for a favourable price. This work can often be undertaken without duplicating inspections, permits and labour.

Do not hesitate to ask the contractor for a clear explanation of any aspect of the work before, during or after the installation of your heating system.