In this guide, you are going to learn exactly how to prime RV water pump for effective and improved performance.

Also covered in this guide are:

  • What does it mean to prime RV water pump?
  • What do you need to prime your RV water pump?
  • What not to do when priming RV water pump
  • And lots more…

Let’s get started.

Also see: How to Refill Fresh Water Tank During Camping

What Does It Mean to Prime RV Water Pump?

How to prime RV water pump
Source: Amazon.com

Being a true lover of recreational vehicles, you must be already aware of how important it is to learn how to prime RV water pump.

But what does priming an RV water pump entail?

As you may already know, every RV water pump tends to run out of pressure and malfunctions if not handled for a long time, especially during winter.

Priming an RV water pump is one way you can use to get the pump going once again.

It entails flushing back into the RV water pump, then forcing through as a means to stimulate more pressure in the pump. The pressure is stimulated until the pump can start pumping again.

Priming an RV’s water pump is not difficult in any way, the challenging part lies in trying to access the pump.

RV water pumps are usually located beneath the bench seats or in the RV’s cabinets so it can be close to the water tank.

If you don’t find it there, open the cabinet underneath the kitchen sink of the RV and trace the water line to where you see the water pump.

When located, priming the RV water pump is much easy to do.

Whether you just newly installed your RV water pump, or have kept it stored up for a while, it’s still essential to prime it before using it.

How to Prime RV Water Pump

Some items you will need when priming an RV water pump include:

  • A jar
  • Flathead screwdrivers
  • Water
  • Rubber tubing

Here are the rights steps to take when learning how to prime RV water pump to get the best performance out of it:

1. Disconnect the Line of the Water Outlet from the RV Water Pump

This is usually done by turning the screw found on the attaching collar counterclockwise until you notice it’s loose enough to pull off the hose easily.

If you are unfamiliar with where the outline is; the outline is that clear plastic line that comes out of the RV water pump and goes back into the RV to feed showers, sinks, and toilets.

2. Slipping the Collar Off from the Outlet Line

The next step to take when learning how to prime RV water pump is to slip the collar off from the outlet line to the end of the rubber hose.

Then look for the specific outlet that spouts on the RV water pump.

Now connect the rubber hose to the outlet by screwing the clampdown. Make sure that the rubber hose is of the same size as the waterline and is long enough to extend out from beneath or behind the exact spot of the water pump.

3. Filling the Jar with Water

Prepare about 12 ounces of water (about a soda bottle full) and use it to fill a jar.

When this is done, hold the hose which you connected to the outlet up in the air in a way that it is above the water pump’s level.

Now pour the water from the jar into the hose.

Place your thumb over the hose to build up pressure for some minutes, then turn on the water pump.

Once you feel the water against your thumb, turn off the pump.

4. Taking the Hose Out of the Pump

After taking the hose out of the pump, reconnect the water line again, open one of the faucets installed in the RV and turn the water pump on.

Once you notice water coming out the faucet after a few seconds, close the faucet and turn the pump off.

A successfully primed RV water pump is one that has water coming out of the faucet after all these processes stated above.

What Not to Do When Priming RV Water Pump

To be sure of a smooth process when learning how to prime RV water pump, here are some tips and warnings that you should focus on:

1. Please make use of hoses that are designed mainly for drinking water to maintain its cleanliness.

2. Considering the amount of water in the freshwater tank is very important, especially if there is just a little amount of freshwater available at the campsite. Water weighs approximately 8 pounds (lbs.) per gallon. Therefore, a 50-lb holding tank can add up to 400 lbs. of water to your RV freshwater tank.

3. Knowing exactly where the water pump in the RV is located should be a major priority when you first purchase a recreational vehicle.

4. If the RV water pump is not easily accessible, the best thing to do is to trace the water line from its specific location to where it connects to a sink. Then remove that line and use it as the rubber hose as addressed in the steps listed above.

5. Pour around a gallon of water to the line instead of a jar full to avoid creating an air trap in it.

6. Priming RV water pump after storing it for a while during winter and using antifreeze in the water lines, leave the faucet open and the pump running until the freshwater from the tank is totally clear. The water produced should also be clear before turning off the faucet and pump.

Note that antifreeze left in the supply of water can lead to certain ailments.

Water pumps play a very crucial role in an RV. There are two types of RV water pumps:

  • Freshwater pumps
  • Macerators

Freshwater RV pumps help to supply a specific amount of water supply every minute for a purpose.

In fact:

Most freshwater RV pumps are capable of supplying about 3.5 gallons of water every minute. But for a larger recreational vehicle, you may require a water pump that can supply up to 5.3 gallons of water every minute.

While freshwater pumps help to supply water, macerators help to supply pressurized water from the RV tank.

RV water pumps’ voltage ratings are basically of two types:

  • 12V RV water pumps
  • 24V RV water pumps.

But a standard recreational vehicle makes use of a 12V battery powered water pump.

See this YouTube video on how to prime RV water pump:


With this guide, you should no longer be bothered about how to prime RV water pump. Simply follow the steps listed in this guide.

Now I would love to hear from you; if you think I missed a few things out, please let me know in the comments.

Also, do not hesitate to leave a comment below if you have any questions on how to prime RV water pump