Federal Energy Efficiency Regulations and their Impact to Commercial Boiler Systems

T. Whitehead, P.Eng.

Enbridge Gas Inc.

The Canadian government, through Natural Resources Canada, sets minimum equipment performance standards (MEPS) through its Federal Energy Efficiency Regulations. This is important to the HVAC industry because these regulations determine what heating and cooling equipment is available for sale in Canada, thus impacting what options contractors have and ultimately the choices available to customers.

The last update to the energy efficiency regulations, Amendment 15, impacted a range of HVAC equipment. For the residential sector, it raised the minimum furnace annual fuel utilisation efficiency (AFUE) from 90 percent to 95 percent. For homeowners, the impact is relatively small with the only major impact being higher priced residential furnaces.

However, for the commercial sector, the impact of Amendment 15 is far greater. Beginning January 1, 2025, commercial gas boilers with input ratings between 300,000 Btu/h and 10,000,000 Btu/h will have a minimum energy performance standard (MEPS) at 90 percent thermal efficiency. This is a significant increase from the previous minimum thermal efficiency of 83 percent. This means any new boiler manufactured after 2025, will be a condensing type - for all installations, including retrofit.

The goals of increasing the MEPs for any equipment is to reduce energy use, energy costs, and greenhouse gas emissions incurred by end users. However, this is only true if the system in which the better equipment is operating allows it to achieve higher levels of efficiency. In the case of commercial boiler systems, there are retrofitting challenges that need to be addressed by engineers and the trades to ensure that condensing boilers operate the way that they are intended. If accompanying changes to the balance of the boiler system are not made, then mandatory condensing levels will lead to extra cost with very little benefit compared to non-condensing equipment that is offered today. We highlight a few of those challenges here.

Condensing boilers offer minimal efficiency gains and savings compared to mid efficiency boilers if return water temperatures are higher than 130F. Return water temperatures need to be lower than 130F for the flue gases to condense to get condensing efficiencies. For buildings that were designed for mid efficiency boilers and older boilers, upgrades to other system components, such as the heat distribution piping and terminal units, may be required to ensure the return water temperature is low enough to allow condensing boilers to condense for a majority of the heating season.

Another challenge may be the venting requirements for condensing boilers in older buildings. There may be issues where access to exterior walls or roof are not possible requiring expensive venting solutions. Single boiler failure and replacement in existing multi-boiler common vented systems which today would be easily handled by a mechanical contractor, could be a major challenge, likely requiring costly professional services and permits. This may include replacing the entire boiler system including all working non-condensing boilers and replacing them with condensing units, or alternatively, designing a boiler system that can accommodate separate venting and plumbing arrangements.

To avoid these potential challenges during a unexpected boiler failure scenario in the winter, contractors and building owners should proactively plan for upgrading their boiler systems to accommodate condensing equipment. This ensures their systems will operate safely and efficiently when the time comes to replace their boiler.  In Ontario, Enbridge Gas’ incentive programs are available to support building owners and their partners with this transition. More information is available at Equipment Upgrades | Enbridge Gas.

About Enbridge Gas Inc.

Enbridge Gas, an Enbridge (ENB) company, is Canada’s largest natural gas storage, transmission and distribution company based in Ontario, with over170 years of service to customers. The distribution business provides safe, affordable, reliable energy to about 3.8 million customers and is leading the transition to a clean energy future through net-zero emissions targets and investments in innovative low-carbon energy solutions. Learn more at enbridgegas.com.

Back to Newsletters