Red Seal Gasfitter — Class B Practice Exam

The typical operating temperature range for gas water heaters generally falls between 120°F to 140°F. This range is considered optimal for delivering hot water for domestic use while also preventing scalding and maximizing energy efficiency. Water temperatures set below 120°F can potentially lead to the growth of harmful bacteria like Legionella, which can thrive in warmer water. Conversely, temperatures above 140°F can be dangerous as they increase the risk of scalding, especially for children and the elderly.

Setting the water heater within this recommended range strikes a balance between safety and effective performance, ensuring that hot water is readily available for various household tasks while minimizing health risks.