ULC C795 PDF 2021

These requirements apply to factory-built gas-fired package boilers having input ratings of more than 117,228 W (400,000 Btu/h), per individual combustion chamber, and intended primarily for commercial and industrial installation.
These requirements also apply to all high pressure steam and high temperature water gas-fired boiler assemblies regardless of kW (Btu/h) input.
Package boilers covered by these requirements are designed to be automatically operated without a competent attendant being constantly on duty at the burners while the appliances are in operation.
Additional installation and operation requirements are available for commercial-industrial gas-fired package boilers as defined by the Natural gas and propane installation code, CSA B149.1, and the Code for the field approval of fuel-related components on appliances and equipment, CSA B149.3, as applicable.