Lethbridge College PE Building
Lethbridge , AB

Lethbridge Junior College opened in 1957 as the first publicly funded community college in Canada. The name of the college was later changed to "Lethbridge College". Over 5,000 students attend the Lethbridge, Alberta, institution.


One of the college's top 2023 Capital priorities was a $1.3 Mill. boiler replacement project.

In this steam to hot water conversion, the three new hot water boilers (Thermal Solutions EVS3000) were located on the far side of the mechanical room from the existing vertical chase. The facilities manager wanted to avoid the use of a power vented system if possible. There were concerns around maintenance of a power vented system and redundancy if a power vented system were to fail. However, the long horizontal runs exceeded the maximum venting length of the boilers. The relatively short vertical, and wide range of boiler outputs, made it challenging to provide sufficient natural draft.


The engineer chose ENERVEX as they were the only manufacturer that was capable of providing a complete solution that fit the wants of the Facility Manager. ENERVEX's engineering expertise was able to work with the boiler manufacturer and the mechanical room layout to provide a solution that met the requirements laid out by the Facility Manager and restricted by the mechanical room layout. The innovative approach to the layout using upsized boiler venting to extend the horizontal runs from the boilers to the base of the common vertical. The use of the SMDS dampers to prevent over-drafting of the boilers during cold conditions and being able to provide the engineering support and documentation provided the engineers with the confidence they needed to specify the ENERVEX system.

ENERVEX equipment used included a 22" EPS1 - Common Vertical chimney, 12" EPS1 - Horizontal runs to each of the three boilers (including eccentric increasers to allow for clearance of the condensate traps) and 12" SMDS - One for each of the three boilers to prevent over drafting and to prevent back drafting on boilers that are not firing.


During the commissioning process, the system worked exactly as it was designed to work. Commissioning was done on a warm day, with the boiler plant operating at 100% capacity, the system drafted as designed and the SMDS dampers operated perfectly to maintain proper pressure at the individual outlets of each of the three boilers.

General feed back from the Contractor: They were impressed with how easy and complete the Enervex system was. General feed back from the Facility Manager: He was impressed by how simple the system was.





Sunwise Engineering (McCall Leavitt / Tenille Camphaug)


KB Heating (Jeff Wiebe)