How to prime a water pump: A complete guide

Priming is an essential step for having your water pumps function properly. Having the knowledge to correctly prime a pump is crucial when using these products for domestic or commercial purposes.

In our complete guide, we’ll take you through the essential steps and tips you need to easily prime your pump. We’ll also explore self-priming pumps such as the Bromic Waterboy™️ range, and how they differ from pumps that require manual priming.

What is water pump priming?

Priming a water pump is the simple process of replacing the air inside the pump with water. This prevents pump failure due to air becoming trapped inside the pump, known as air locking.

Pump priming takes place upon set-up, and pumps may need to be reprimed in some cases. This may be because the pump has sat idle for a period, or because air has somehow made its way into the pump.

Many pumps on the market are self-priming. These pumps use an automatic priming process when set up, and generally don’t need to be subsequently primed. For example, Bromic Waterboy™️ jet pumps begin self-priming when a foot valve is connected.

However, even if you use a self-priming pump, it can still be very useful to know how to prime a pump if the need ever arises.

How to prime a pump

Below is a typical process for priming many types of water pumps on the market. Keep in mind that methods can vary from one pump to another. Be sure to consult your manufacturer’s instructions before priming a pump.

1. Disconnect the pump from the power supply. This is important for preventing any damage to the pump.
2. Close the valve connecting your pump to the water supply (intake valve).
3. Open any relief valves on your pump.
4. Open the priming port on your pump. This may involve removing a bolt or other element.
5. Fill your pump casing with clean water via the priming port. Some pumps may require the casing to be completely filled, while others can successfully prime with the casing only partially filled.
6. Close your priming port, taking great care to ensure it is properly sealed.
7. Open the intake valve between the water supply and the pump.
8. Close the pump’s relief valves.
9. Restore power to your pump. It should now begin functioning as intended.
10. Observe the pump’s function and water pressure gauge to ensure it is working properly. If the priming is successful, the pump should turn itself off when complete.

Pump priming trouble shooting tips

Pump priming not working properly? Here are a few common reasons it may be failing, and what you can do to resolve each issue:

Air leaks

If there are air leaks present, your pump will be unable to achieve the required suction to prime. Signs of air leaks include an inability of the pump to draw water or an intermittent flow. You may also notice a hissing sound near joints and bubbles in the pump or hoses.

If you suspect an air leak is interfering with your ability to prime your pump, inspect all connections, fittings and the priming port for loose seals. Ensure they are properly tightened.

You should also inspect hoses or pumps for any cracks.

Insufficient water

For a pump to prime, it requires a minimum amount of water. Failure to prime may be a sign that your pump does not contain enough fluid to complete the process.

You might notice this occurring due to the pump making irregular noises, or if there is little to no water exiting the pump. You can generally resolve this issue by refilling the pump with water through the priming port.

Keep in mind that for many pumps, the casing must be completely filled for it to successfully prime.

Closed intake valve

Unsurprisingly, if your intake valve is not open, you will not be able to prime your pump. Signs of a closed intake valve include limited water flow, possibly accompanied by abnormal vibrations.

To solve this issue, simply ensure that your intake valve is open and restart the priming process. If your valve is stuck or difficult to open, apply lubricant or replace it if it is damaged.

Distance

Tried a number of fixes, but your pump is still struggling to pull water? There may be too much distance between your pump and the water tank or source. This means that your pump requires too much suction lift to prime and function.

If possible, simply move your pump closer to the water source. This will reduce the suction lift and hopefully allow you to proceed with priming your pump. If your pump can’t be moved, consider installing a booster pump to lift water a greater distance.

Trapped air

For priming to be successful, all air must leave your pump. If trapped air remains in the pump, you may notice water failing to travel through your pump. Water flow may be uneven or spluttering.

If you believe air may be trapped in your pump, ensure release valves on your pump are open. If the design and use of your pump support it, you can try gently shaking or tilting the pump.

If your system is using multiple pumps, check that all vents and valves are open on each pump. Once you’ve successfully applied one of these fixes, you can usually simply restart the priming process.

The advantages of self-priming pumps

Don’t want to deal with the priming process and everything that can go wrong? Many pumps on the market are now self-priming, meaning that the priming process is vastly simplified.

Self-priming pumps have several benefits, including:

• Easy set-up: Self-priming pumps are generally much easier to set up than other types of pumps. This is especially important if you are unfamiliar or inexperienced when it comes to setting up a water pump.
• Ideal for intermittent use: If a pump is intended to sit idle for long periods of time, a self-priming pump is often the best option. If a non-self-priming pump is left idle for a long period, it may need to be re-primed. This is not an issue for a self-priming pump.
• Deal with air in fluid: Self-priming pumps are able to deal with air in fluid, as they can be automatically re-primed when necessary. When a non-self-priming pump encounters air in its pump housing, it may lose its prime and need to be manually re-primed. This makes self-priming pumps far more practical than alternatives on the market.
  In many cases, the best approach to water pump usage is to opt for a self-priming pump, while having the knowledge to manually prime a pump. This can become relevant if the priming mechanism of a self-priming pump fails.

Browse Bromic water pumps

The Bromic Waterboy™️ range contains a number of submersible and jet pumps, suitable for a wide range of purposes. With a super simple self-priming set-up, it’s easy to install and get started with your water pump.

Bromic supports customers with in-depth technical documentation and support. We have the knowledge you need to undertake successful water pumping tasks.

Browse Bromic water pumps today and find the self-priming water pump you need for your next project.