When troubleshooting an insufficient heat call, which item should be checked first?

In the context of troubleshooting an insufficient heat call, the aqua stat is a crucial component because it directly regulates water temperature in heating systems, particularly in hydronic systems. If the aqua stat is malfunctioning, it may fail to provide the necessary signal to activate the burner, which can lead to insufficient heat output. Checking the aqua stat first allows the technician to determine if the system is receiving the correct temperature readings and ensuring that the heating element is functioning properly.

While it is important to consider the other potential issues such as air in the loop, under firing, or problems with the thermostat, these can typically be assessed after confirming that the aqua stat is working correctly. By prioritizing the aqua stat, technicians streamline the troubleshooting process and can more effectively identify the root cause of the heating issue.