Tank Fill / Recirculation

The Recirculation Loop

The tank-fill valve creates a water path from the pump discharge back into the booster tank. When no discharge lines are open, the pump would otherwise be spinning against a dead-end system — churning the same water over and over, rapidly building heat. By cracking the tank-fill valve open, you create a small circulation loop: water moves out of the pump through tank-fill and back into the tank, then back out to the pump via tank-to-pump. That constant movement removes heat from the pump casing.