Which is mandatory to have installed on a separate connection on a hot water heating boiler?

The requirement for a thermometer to be installed on a separate connection on a hot water heating boiler is rooted in safety and operational efficiency. A thermometer allows for the accurate monitoring of the water temperature, which is critical for ensuring that the boiler operates within safe parameters.

Maintaining the right temperature is vital for preventing overheating, which can lead to pressure build-up and potential hazards. Additionally, knowing the water temperature assists in optimizing the heating process, ultimately enhancing the system's performance and energy efficiency. This monitoring is especially important in a closed-loop system, where temperature control significantly affects the comfort and safety of the heating system.

In the context of boiler operation, other instruments like a pressure gauge, expansion tank, and flow meter serve important functions, but they do not have the same mandatory requirement for separate connections as a thermometer does in relation to monitoring water temperature effectively.