How is the water flow in a hydronic heating system checked?

In a hydronic heating system, checking the water flow is precisely done by measuring the pressure drop across the water pump and comparing it to a pumping performance chart. This method provides a reliable indication of the system's efficiency and operation.

When measuring the pressure drop, you can determine if the pump is functioning correctly and whether there are any obstructions or issues within the system, such as clogs or leaks. The performance chart offers benchmarks that can help identify if the pressure drop falls within acceptable limits, thus confirming that water is flowing efficiently throughout the system.

Choosing this method over other options is crucial because simply feeling the temperature of the pipes does not provide a quantitative measure of water flow; it can only give a general sense of heat transfer. Monitoring the temperature at the outlet also doesn't directly indicate the flow rate, as it can be influenced by various factors like system design and load. Finally, checking the flow rate at various locations can be useful but lacks the direct correlation and comprehensive understanding provided by analyzing the pressure drop against the performance chart. Thus, measuring the pressure drop is the most effective and widely accepted method for evaluating water flow in hydronic heating systems.