Final answer:
A dishwasher may need a built-in thermometer to ensure that water temperatures meet the required sanitizing levels, especially in commercial settings. Residential dishwashers typically rely on the home's water heater, but some models contain sensors for improved performance.
Step-by-step explanation:
Whether a dishwasher needs to have a built-in thermometer to check water temperature at the manifolds depends on the specific requirements of the dishwasher's design and intended usage. In many commercial settings, such as restaurants and hospitals, where sanitization is critical, having precise temperature control and verification is essential for health and safety regulations. Industrial dishwashers often do have built-in thermometers to ensure they meet the required sanitizing temperatures as mandated by health codes, which commonly stipulate that the water must reach a certain temperature, often around 160 to 180 degrees Fahrenheit, to effectively sanitize dishes.
In residential dishwashers, built-in thermometers are less common, and the machines rely on the home's water heater to provide water at the appropriate temperature. However, some high-end or feature-rich home dishwasher models might include temperature sensors to enhance performance or for energy-saving purposes. Regardless, ensuring proper water temperature is crucial for the dishwasher's ability to clean and sanitize effectively.