What It Means When Your RV Water Pump Pulses


If you’re an avid RV’er like us or someone who’s just getting started, which was us not too long ago, you know the importance of having a working water system. Being able to store and pump water to your sinks, toilet, and shower are crucial to an enjoyable trip in your RV. That said, there are a number of common issues associated with RV water pumps to watch out for.

A pulsing RV water pump is a fairly common occurrence, and not necessarily an indication of the system malfunctioning. The pump will pulsate when it is trying to regulate the water pressure while the system is in use. Pulsing simply means that the system is fluctuating between high and low pressure.

While a pulsing RV water pump isn’t necessarily a problem that needs to be fixed, it’s an annoyance that can be addressed. Before deciding if you need to tackle the problem though, you might want to learn more about why it’s occurring in the first place.

What Causes an RV Water Pump to Pulse?

Your RV’s water pump is tasked with maintaining the water pressure in your pipes, such that if you’re running water through the kitchen sink your pump is working to make sure that water is being delivered. Because of this, the pump is designed to only run when water is being run.

When you run water in your RV, you probably hear the pump kick on to compensate for the loss of pressure in the system. If you’re running the sink at full draw, the pump will run continuously, as the demand to maintain high pressure is higher.

Your RV’s water pump might start to pulse is if your water is flowing at a lower rate than full draw. Because there isn’t a continuous, high demand on the pressure in the system, your water pump might alternate between on and off as the demand fluctuates. This alternating between on and off can create a pulsing effect.

Again, this is a fairly common occurrence and not something that necessarily indicates a problem in the system. For many RV owners, this is just a quirk of living in an RV and just becomes part of the background noise.

Learn more about the basics of How an RV Water Pump Works as well as How to Care for You RV Water Pump in our articles.

Are There Other Causes of the Pulsing?

While the most common cause of a pulsing RV water pump is simply a fluctuating demand on the pressure in the system, there are a few, less common causes that might indicate a more significant issue with the system. These include:

  • A leak in the system: If your system has a leak in it, then your pump could have a hard time maintaining the pressure within the system. While it might not be a leak large enough to let out enough water to cause you to notice, any sort of leak in the system will allow pressure to drop in the system. If you think this is the case, you’ll need to check your entire system for the leak, including the pump itself, filters, and the piping.
  • The tank is too low: Another possible reason for the pulsing of your water pump is that the tank is too low on water. A commonly reported issue by RV owners, the water tank being too low might cause your water pump to struggle when drawing water from it, thus causing it to pulse as it works to compensate for what it thinks is low pressure.
  • A blockage in the system: Another potential cause of the pulsing in your water pump is a blockage somewhere, most likely the filter, in the system. Blockages in the filters of your RV’s water system can’t cause the water to flow less consistently through the system, confusing your water pump as to what it ought to be doing. This can be fixed by simply checking and cleaning out your system’s water filters.

Is There a Way to Stop the Pulsing in My RV Water Pump?

While a fairly harmless but common problem, the pulsing can be an annoyance to live with. Thankfully, there’s a solution to this problem. An accumulator tank can help to regulate the pressure in your RV’s water system and help it the pump run more smoothly.

SHURflo 182-200 Pre-Pressurized Accumulator Tank,Black, 9.1" x 4.8" x 3.8"
  • Reduces pump cycling
  • Smooths water faucet pulses
  • Pre-pressurized to 30 PSI with built-in diaphragm

An accumulator tank is a small reservoir made of plastic that contains a pressurized bladder inside it. This pressurized bladder is what allows the accumulator tank to absorb and regulate spikes and drops in pressure in the system. As the pump runs, the pressure within the pressurized bladder will fluctuate to maintain a constant pressure level within the system.

This helps to mitigate the spikes and drops that might otherwise occur in your system that cause the pulsing you’re experiencing.

There are a number of pros to installing an accumulator tank, the first and foremost being the reduction in the pulsing issue. Equally important however, is the accumulator tank’s ability to reduce the amount of cycling your pump has to do and thus reducing how often it runs.

Because the accumulator can absorb much of the drop in pressure experienced from running the tap, your pump will have less work to do to maintain the proper pressure level.

Another benefit of an accumulator tank is an increase in the life of your pump. It stands to reason that if your pump has to work less often and not as hard when it does run that it will extend its lifespan. An accumulator tank reduces your pump’s workload and helps achieve a longer pump life.

Lastly, an accumulator will help to reduce the drain on your battery from using the water system. Because an accumulator tank only uses the pressurized bladder to do its work, there’s no power supply needed. And, by reducing the amount of time your pump will need to run, you’ll easily reduce the amount of power used by your water system.

Are Accumulator Tanks Hard to Install or Expensive?

Accumulator tanks are simple to install to your water pump. Because of their small size, they can be installed essentially anywhere within your plumbing system on the pressurized side.

In terms of price, accumulator tanks are fairly affordable. Ranging anywhere from $30 to $100, the price will depend on the size and quality of the materials used. You can find them easily here on Amazon. The more expensive models tend to be made with more durable materials for a longer lifespan.

Is the Pulsing a Bad Thing?

The pulsing you may experience from your RV’s water pump is a fairly common and harmless occurrence. While creating a fairly annoying sound and an inconsistent water flow when the tap isn’t at full draw, these are both surface level problems and not issues that will create larger problems.

That said, the inconvenience can be very irritating. This can be especially true if your pipes are rattling because of it. In some instances, the pipes in an RV are set too close to each other or a wall. When this pulsing occurs, it can cause the pipes to shake.

If they’re situated too close to each other or a wall they could rattle off of that and create an even louder and more annoying noise than the one caused by the pulsing pump in the first place. We have found this in our own RV and had to resecure the pipes connecting to the pump to reduce the rattle from the pulsating pump.

Rattle can be reduced by adding some insulation to the pipes. Adding a soft layer of insulation to the pipes causing the rattling noise will help to deaden or eliminate the noise entirely. Of course, simply installing an accumulator tank is probably an easier solution than opening up the walls and adding insulation to all of your pipes. Then again you may only need to add insulation to the pipes connected directly to your RV’s water pump.

Duck Brand 1285244 Pipe Wrap Insulation for Hot or Cold Pipes, 3-Inch Wide x 1/11-Inch Thick x...
  • Insulates hot and cold pipes
  • No gloves or masks needed
  • Fiberglass-free material so you can install by hand without irritation

Recommended Products for RV Water Pumps

Diane Dee

Diane is a lover of all things travel. She and her young family wanted to explore North America from the comfort of their own home so they bought an RV. After fully rehabbing a 1994 Safari Trek, they set out to explore both Canada and the USA.

Recent Posts

RV water pumps are notorious for being noisy. Most of the time this pulsing and noise from your campers pump is normal but there are a few tips you can do to quiet your trailers water pump. #rving #rvliving #rvmaintenance #rvsystems