What is the standard maximum temperature setting for domestic hot water?

The standard maximum temperature setting for domestic hot water is typically 60°C (140°F). This temperature is recommended primarily for safety reasons, as it helps to minimize the risk of scalding injuries, which can occur at higher temperatures, particularly in systems accessible to children and the elderly.

Additionally, maintaining hot water at this temperature can help to prevent the growth of harmful bacteria, such as Legionella, which can thrive in water temperatures below 60°C. However, water below this temperature has a higher risk of bacterial growth, while water above it may pose a danger if there are no safety measures in place to prevent scalding.

While some higher temperatures are provided in the options, they generally increase the safety risks associated with domestic hot water usage. Therefore, the ideal standard for residential hot water systems aims to balance safety and effectiveness within the recommended limit of 60°C.