Boiler Wiring Diagrams 101: Symbols, Switches & Fast Fixes

In this installment of Weekly Boiler Tips we cover how wiring diagrams work, the most common switches and symbols, and how to test limits to build your own reference guide.
Sept. 17, 2025

Troubleshooting without a wiring diagram is like flying blind. In this installment of Weekly Boiler Tips we cover how wiring diagrams work, the most common switches and symbols, and how to test limits to build your own reference guide. A must-watch tip for anyone responsible for keeping boilers online. Safety notice: Always consult experts for complex repairs. Weekly Boiler Tips are compiled by the knowledgeable and remarkably prolific content creators at WARE, a family owned, third-generation, 69-year-old commercial and industrial boiler rental and service firm based in Louisville KY. You can learn all about this and more at WARE's Boiler University.

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