RV Water Pump Keeps Running (Causes & Fixes)

It can be a nerve-wracking feeling to have an RV water pump that keeps running when it should have turned off. It’s easy to fear the worst if you’re not familiar with RV plumbing, but don’t pick up the phone to call for help right away! With some insight on how water pumps work and a checklist of what to look for, you can fix the problem like a pro.

RV water pumps will keep running when the pressure within the water system drops. This happens when there is a leak in the water lines, a crack in the valve, or when the water pump becomes faulty. Fixing the damaged component will restore pressure and allow the water pump to turn off when not in use.

Although fixing an RV water pump may initially seem intimidating, a step-by-step process of elimination can help us determine the root of the problem. This article will explain what an RV water pump is, how it works, and the steps you can take to fix a water pump that keeps running.

What is RV Water Pump?

One of the perks of traveling with an RV is having running water on hand, even when a city water connection isn’t available. Water is stored in an onboard fresh water tank and an RV water pump delivers it to all of the faucets and water-consuming appliances in the vehicle. A water pump that keeps running can affect the delivery of water to several appliances, including:

  • Faucets
  • Showers
  • Toilets
  • Washing machines

RV water pumps are located just outside of the water tank, where they pull water through themselves and into pipes that disperse it throughout the RV. 

Since RV water pumps get a lot of use, they also frequently encounter issues, one of the most common issues being a water pump that continually runs. Luckily, problems with RV water pumps tend to be easy to diagnose and repair, often without the need for professional help. 

How Do RV Water Pumps Work?

To avoid unnecessarily spending money on professional repairs, it’s important to understand how RV water pumps work. 

Water pumps are intended to run on-demand. The mechanism that controls the pump pressurizes the pipes. When a faucet is turned on, the pump senses a drop in pressure, which prompts the water pump to turn on and push water through the lines. 

When the faucet is turned off, the water pump will continue to run until the proper pressure is reached before it turns off automatically. However, if the water pump continues to run, or if it continually turns off and on again while all faucets are turned off, it is often an indication of a leak that is depressurizing the system. 

What Causes RV Water Pump To Keep Running?

There are several reasons why an RV water pump may keep running, and figuring out the source of the problem comes down to a process of elimination. 

If a water pump continues to run when there is no water flowing, it is due to one or more of the following problems:

  • A lack of water in the freshwater tank
  • A broken check valve
  • A leak in the water lines
  • A faulty water pump

Let’s take a look at how to use the process of elimination to inspect your freshwater system and determine what’s causing your RV water pump to keep running. 

How To Fix RV Water Pump That Keeps Running?

How to fix an RV water pump will depend on what is causing the issue. Pumps continue to run when they sense a lack of pressure, but this lack of pressure can come from several different parts. Let’s take a look at the most common causes of a malfunctioning RV pump and how to go about fixing each one. 

Lack of Water in the Freshwater Tank

If your RV water pump sounds like it’s running, yet no water is coming out of any faucets, then the first thing to check is your freshwater tank. Freshwater tanks have a limited capacity, and it may be possible that you’ve run through your reserve faster than anticipated. 

If the water level is low, or if you are parked on a slope that moves the remaining water supply to one side of the tank, then the water pump may not be able to access the water. This would cause the pump to pressurize the lines without being able to pump any water through them. 

In this case, simply filling the water tank will get your water pump properly working again. However, if your freshwater tank is reasonably full and the pump continues to run, then something else within the system is malfunctioning. 

Broken Check Valve

The check valve of an RV water pump regulates the water flow. It allows water to exit through the valve and into the water lines while also keeping it from flowing backward into the freshwater tank. When the check valve is cracked, however, it is unable to keep water from cycling back into the tank, in turn causing the pump to keep running. 

To determine whether the check valve on your RV water pump is cracked, the first thing to do is to turn the water off. You can then inspect the valve, which usually sits next to the hose that connects the water pump to the fresh water tank. If you find that it is cracked or otherwise damaged, you will need to replace the valve. 

Leak in the Water System

A leak in the water lines can cause the water pump to sense a lack of pressure. Because water pumps are run by a sensor, this lack of pressure will cause them to turn on in order to bring the pressure back up to where it should be. As the pressure escapes through the leak in the lines, the water pump will sense the depressurization and turn on once again. 

The first place to check for a leak is in the water lines themselves. Look for any loose connections, cracks, or splits. Turn a faucet on to get water flowing through the lines while you inspect them for an easy way to find leaks wherever water drips. 

If there is no indication of a leak in the water lines themselves, then move on to check the connection between the fresh water tank and the water pump. To do so, turn off the water and carefully disconnect the line. If the line is dry, then there is likely a crack or clog in the line leading to the tank. If there is a stream of water, then the problem may be with the water pump itself. 

Faulty Water Pump

A faulty water pump implies one of two things – either the compromised component within the pump must be repaired, or the pump will need to be replaced entirely. Those who are handy with some basic tools can attempt to take the pump apart to find the malfunctioning part. If you don’t feel confident in doing so, then it may be time to call a professional. 

Alternately, buying a new water pump may be a quicker and cheaper option. Prices range from less than $100 to slightly over $200, and installation will almost certainly be a faster process than taking the pump apart. 

How to Replace an RV Water Pump?

Always follow the manufacturer’s instructions when replacing an RV water pump as it may vary between models. However, the following steps are a general guide to help you understand the process. 

Step 1: Empty the freshwater tank

To empty the freshwater tank, first connect a hose to the base of the tank. Once the hose is securely connected, open the valve to release the water. 

Step 2: Disconnect the old water pump

The first step to disconnecting your old RV water pump is to be safe by disconnecting the RV battery. 

With the batter disconnected, disconnect the hoses that connect the old water pump, and remove the black and red wires with a screwdriver. Once the hoses and wires are removed, you can disconnect the pump itself by removing the bolts and screws that hold the pump in place. 

Step 3: Connect the new RV water pump

To connect the new water pump, position it in the same place as the old one and fasten the bolts and screws to keep it in place. 

Reconnect the hoses and secure them with clamps. Make sure that the line between the freshwater tank and the water pump is secure before reconnecting the wiring. Once everything is in place, you can reconnect the RV battery. 

Step 4: Test the connection

Turn on your RV to test the water pump. If you can hear the pump working, you know that you have reconnected it properly. If it does not turn on, go back to check that all hoses and wires are connected and secure. 

Step 5: Test the water pump

Once your RV water pump is connected, you’ll want to make sure that it is working properly. To do so, fill the freshwater tank with sufficient water for the pump to reach it, then turn a faucet on. Check for any leaks and ensure that water gets pumped through the lines all the way to the open faucet valve.  

Remember that you are starting with empty water lines, and it may take a moment for the water to reach the faucet. 

Wrap Up

An RV water pump that keeps running is commonly caused by a loose connection or a damaged part that releases the pressure within the system. When that’s not the case, it may be time to replace the pump entirely.

Although problems with RV water pumps can be easy to fix, there are many parts involved in the freshwater system, including some electrical components. Always keep safety as a priority and, when in doubt, call for professional help.  

Leave a Comment