The priming pot also known as priming chamber is used for priming the pump in the event of negative suction condition. This avoids the need of foot valve and frequent priming of the pump.

The priming pot is connected to the pump suction filled with liquid and sealed airtight before initial start up. After starting the pump, the liquid from priming pot is drawn into the pump and partial vacuum, is created in the pot. Due to partial vacuum, liquid rises in the suction pipe and pushes the air into the pot. This action fills the suction pipe resulting in priming. The air accumulated in the priming pot mixes with liquid and is driven through discharge of the pump. Thus, the priming pot is filled and is ready again for the next start up.