The Steam Engine Safety Valve: New Valves Require Knowledge of Old Boilers

What you need to know before buying a valve for your hand-fired boiler

Safety-Value_no-nos
Two examples of what not to do when installing a safety valve. Don't use any fittings smaller than the inlet to the safety valve, as at left. At right is another no-no: Don't install any kind of valve between safety valve and the boiler.
Figures courtesy of Bruce E. Babcock