Boilers

One of our engineers installing a boiler

Over the last 20 years, a new generation of higher-efficiency gas boilers has come to market. The newer designs have been modified to increase energy efficiency by reducing the amount of heated air that escapes and by extracting more of the heat contained in the combustion by-products before they are vented.

Residential non-condensing gas boilers sold in Canada today are required to have an annual fuel utilization efficiency (AFUE) rating of at least 80%. ENERGY STAR® qualified boilers must have an AFUE rating of at least 85%.

The following are some ways manufacturers have improved efficiency levels:

  • Elimination of continuous pilot lights - Most boilers on the market today use some form of intermittent ignition device, usually electronic ignition.
  • Improved insulation levels - To reduce heat lost from casings, new boilers have much better insulation to keep the boiler water hot.
  • Better draft control methods - Many boilers use draft hoods to help stabilize airflow. Others use aspirating gas burners which eliminate the need for a draft hood entirely by using a powered exhaust system.

Condensing gas boilers can offer an even higher AFUE rating (90% or higher) as they have an additional heat exchanger to help extract latent heat remaining in combustion by-products.

Integrating space and water heating in a single appliance

In many cases, new or renovated houses have reduced space heating loads to the point where it is difficult to justify the expense of a high-efficiency furnace solely to satisfy the heating load. To take advantage of the efficiency potential it makes sense to combine space heating with other functions, in particular, water heating.

An integrated, high-efficiency space and water heating system can:

  • Offer efficiencies of over 90% for both space and water heating.
  • Be less expensive than the individual appliances.
  • Eliminate the need for multiple exhaust systems.
  • Maximize efficient operation.

Other options such as a standard-efficiency system or a standard-efficiency boiler coupled with an external storage tank also exist, although their efficiency potential is lower. Your Woodbridge ClimateCare professional can help determine what will work best for you.