Red Seal Plumbing Practice Exam

What must be determined prior to selecting a hydronic circulator?

1. Pipe material and size

2. Boiler capacity

3. System resistance and flow rate

4. Number of radiators

The correct answer is: System resistance and flow rate

A hydronic circulator is an essential component of a hydronic heating system and is responsible for circulating hot water through the system. When selecting a hydronic circulator, it is important to determine the system's resistance and flow rate. This is because the circulator's performance is directly affected by the pressure and flow rate of the system. Options A, B, and D are not the most important factors to consider when selecting a hydronic circulator, although they may play a role in the overall design and functionality of the system. Pipe material and size may affect the overall system pressure and flow rate, but this will also be determined by the resistance and flow rate of the system. Boiler capacity is also not directly related to the performance of the circulator, although it may need to be considered when determining the flow rate and size of the circulator needed. The number of radi