November 2004
The National Research Council (NRC) Standing Committee on Building and Plumbing
Services recently adopted a change to the Plumbing Code that requires water
supplied by fittings in residential buildings to be limited to a maximum
of 49° C (120° F).
This change
will be adopted only for new construction. However, it does not
set the accepted best practice for water temperature control
for all water heater installations. The higher the water temperature
the shorter the time taken to scald. Water stored at 49° C (120° F)
or less can provide ideal conditions for the growth of legionella
bacteria within the water heater.
