Sources
Are Triangle Tube Challenger boilers discontinued?
- Ductless.ca, Triangle Tube boilers page: Challenger discontinued, replaced by Prestige or Instinct
https://ductless.ca/products/triangle-tube-boilers/ - TriangleTubeParts.com, shutdown and leftover-stock notice (as read October 6, 2026)
https://www.triangletubeparts.com/