What is the minimum recommended pressure differential for a water feeder supplying water to the boiler?

The minimum recommended pressure differential for a water feeder supplying water to the boiler is 10 psig because it ensures that there is a sufficient flow of water into the boiler system to maintain its operation effectively. This pressure differential helps prevent issues such as water starvation, where the boiler may not receive enough water to generate steam, potentially leading to overheating or damage.

Having a differential of 10 psig is a standard practice that accounts for factors such as system resistance and fluctuations in pressure. A too low differential may not overcome the pressure in the boiler or may lead to inefficient water feed, which could adversely affect boiler performance and safety.