Self Priming Pumps

About Air Operated Diaphragm Pumps


As a leading supplier of industrial pumps in Australia and New Zealand, Hunter Pumps Industrial has built a reputation for delivering the best equipment on time and to specification. We specialise in providing a wide range of pump solutions, including the best self-priming pumps from some of the world’s most trusted brands. Our expertise lies in understanding the unique needs of our clients and offering tailored solutions that enhance operational productivity and efficiency.

What Is a Self Priming Pump?

A self-priming pump is a specific type of liquid pump designed to be installed high and dry above the fluid level. It operates by removing air from the suction line and filling its cavity or pump body with liquid without manual priming. This process enables the pump to function quickly and efficiently, eliminating the need for a foot valve or a hydraulic column of fluid in the suction line.

Self-Priming Pumps Features and Benefits

How Does a Self-Priming Pump Work?

Keep in mind that self-priming pumps are designed to contain enough water to self-prime before being energised. Running a self-priming pump empty can lead to mechanical seal failure and damage to internal components.

When starting an empty self-primer, it must be primed manually, ensuring adequate water is present in the pump housing.

The self-priming pump operates in two stages:

  • Priming mode
  • Pumping mode

In the priming mode, it works as a liquid ring pump. The pump impeller, powered by an electric motor or engine via a shaft, begins rotating. This rotation creates a vacuum in the impeller’s eye, drawing external high-pressure air from the suction line into the pump.

Simultaneously, this air forms a cylindrical liquid ring within the pump housing, establishing an air-tight seal preventing air from re-entering the suction line from the discharge line.

Air bubbles, trapped within the fluid inside the impeller blades, are transferred to the outlet valve, where the air expels, allowing the fluid to return to the reservoir or “suction chamber” under gravity.

As the air is removed, the fluid gradually rises in the suction line, replacing the air until the suction line and pump are full. At this stage, the normal pumping mode commences, and fluid discharges.

If the discharge valve cannot expel the air, a bypass line may be employed to empty it. Once turned off, the pump retains enough water for the next operation, priming itself until it is fully primed again.

Methods of Priming

The priming of a pump, which can be done by an external source, through design considerations, or using a self-priming pump, is a crucial process to ensure optimal operation. There are several methods of priming, including:

Manual Priming
Priming with Vacuum Pump
Priming with Separator

The priming of a pump, which can be done by an external source, through design considerations, or using a self-priming pump, is a crucial process to ensure optimal operation. There are several methods of priming, including:

Industry Applications for Self-Priming Pumps


Premium Self-Priming Pumps at Hunter Pumps Industrial

Hunter Pumps Industrial is your go-to source for premium self-priming pumps from globally trusted brands. We’ve partnered with industry leaders like Gorman Rupp, known for their superior self-priming centrifugal pumps, and Remko, a top Australian manufacturer of high-quality self-priming pumps.

Our extensive selection also includes readily available spare parts for emergencies. And our team of trained and experienced experts stands ready to provide quick and effective field servicing for your Self-priming Pump needs. 

Connect with us for assistance with pump selection.

Ask our team of specialists

Get in touch with Hunter Pumps to schedule your free pump assessment

Contact Hunter Pumps today

Frequently Asked Questions (FAQs)

Unlike a standard centrifugal pump, a self-priming pump can prime itself without external assistance. This is possible due to a re-circulation system that creates a vacuum, drawing the fluid into the pump. The pump then separates the air from the fluid, expelling it through the discharge. The fluid is pumped through the system, operating like a standard centrifugal pump.

Self-priming pumps are built to handle fluids with solids or air, reducing maintenance needs. However, regular maintenance is still necessary for optimal efficiency. Maintenance tasks may include cleaning the impeller, checking the suction line for clogs, and inspecting the pump for signs of wear or damage.

Self-priming pumps can save labour by eliminating manual priming, which can be time-consuming and labour-intensive. With their ability to automatically prime and re-prime, they require minimal human intervention, freeing workers to focus on other tasks. This saves time and reduces labour costs, making self-priming pumps a cost-effective solution for various applications.

Hunter Pumps Industrial partners with some of the world's most trusted brands to supply a wide range of self-priming pumps. We proudly offer robust pumps from Remko and Gorman Rupp, designed with unique capabilities to suit a variety of applications. For more specific brand information, please visit our website or contact us directly.

Indeed, this self-priming pump can be set up in a dry zone above the sump as long as the suction lift height doesn't surpass 8m. A surface-mounted pump presents numerous advantages compared to a submersible pump, with one key benefit being its accessibility and ease of maintenance.

Fundamentally, all positive displacement pumps are self-priming. This prominently includes rotary gear pumps (both internal and external), lobe pumps, vane pumps, and diaphragm pumps. In all positive displacement pumps, a common feature is the use of close-tolerance parts to prevent fluid from flowing back from the discharge side to the suction side.