These pages are from Nash Engineering Company's Bulletin #402-D describing their variable vacuum sub-atmospheric steam heating controls using their own vacuum and condensate pumping equipment. Thank you to Dennis Pataki for sharing this document.
This document contains the manufacturer's instructions for the HB Smith Series M450L Mills Water-Tube Boiler for automatic firing with oil or gas (Steam, Vapor, or Water ...
This document contains the jacket assembly instructions for the HB Smith Series 45 Mills Boiler (circa 1979).
This document contains the combustion chamber assembly instructions for the HB Smith Series 45 Mills Water-Tube Boiler for automatic firing with oil or gas (Steam, Vapor,...