To limit the probability of excessively high water temperature, which could lead to excessive pressures in pipe systems, which could lead to failure of joints, heating coils or storage tanks, which could lead to exposure to hot water, which could lead to harm to persons.
To limit the probability that the water temperature will exceed the maximum temperature permitted by Sentence 9.31.6.1.(1), which could lead to scalding temperatures at faucets, which could lead to harm to persons.