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Key Takeaways

  • There could be a few reasons why your RV's water pump is pulsating when you turn it on.
  • Some issues are easier than others to fix while others may be a priority to prevent damage.
  • The most common reason for pulsating is that the pump itself is malfunctioning; the pressure switch or diaphragm is defective, or there's something obstructing the inlet and outlet ports.

If your RV water pump is pulsating it could be a few different things causing the issue, but it is worth it to investigate and prevent future damage.

When an RV water pump pulsates, it's usually on account of one of three issues: the pump itself is malfunctioning; the pressure switch or diaphragm is defective; or there's something obstructing the inlet and outlet ports. There could also be an issue with the seals.

When I bought my vintage RV I had prepared for a long time. When I started using the pump it would pulsate and I didn't even know that was an issue. The reason could be something mundane, but it goes to show that there is always more to learn.



Why Do RV Water Pumps Pulsate

When you hear your RV water pump pulsating, it means the pump is trying to get more power than it really needs. The pump can't keep up with the water demand and is trying to pull too much water out of the tank. This is a sign of low pressure because there isn't enough water in your system to fill up all of its parts.

When your RV water pump pulsates, you need to adjust the pressure. The RV water pump pulsating is a tell-tale sign that the pump can't keep up with the water demand.

When an RV water pump pulsates, it's a sign that the pump can't keep up with the water demand. That may be because it needs to do more work than it was designed to handle, or because there's too much pressure in your plumbing system.

The first possibility is easy enough to remedy: if you need more power than what's available at your campsite and can't change anything about your setup (that includes upgrading your RV), simply hook up to shore power using a 30-amp generator extension cord.

This will give you access to an outlet where you can plug in a higher-capacity portable unit like this one from Generac that delivers 1/3 HP and 4 gallons per minute of output flow rate—enough for most RVs' needs.

You might think that since this portable generator delivers only 1/3 HP, it wouldn't be able to push through as much water as other models on our list—but let me assure you: there are no problems here, So don't worry too much about how much pressure they'll require; they'll take care of themselves while providing everything else necessary for good hydration during long trips across America’s great open road.

Other Reasons an RV Water Pump Pulsates

If your RV water pump is pulsating, here are a couple of things you can check.

Check for obstructions. If there is some kind of obstruction in the water system, it might be causing the pulses.

For example, if you have a fishing line or ribbon wrapped around the suction line or discharge hose, this could cause a pulsing action on your RV water pump as well. You can remove these types of items from your system by simply disassembling them and discarding them out of reach so that they are not easily accessible by pets or children (or guests who want to put their feet in the sink).

Check the pressure switch and diaphragm.

Sometimes an obstruction can be caused by a malfunctioning pressure switch or diaphragm inside an RV water pump assembly that causes too much stress on either end of these pieces of equipment—which can lead to premature wear & tear over time! So make sure they're working properly now before investing more money into repairing/replacing them later down the road.

TroubleShooting A Buzzing RV Water Pump

Check all other parts inside

Make sure there's nothing blocking the pump's inlet and outlet ports.

If the water pump is not blocked, you'll have to check the hose connections. Make sure they are clear of debris and that they're locked onto the fittings firmly. Then, check the pump's pressure switch or control relay valve. If either one is faulty, it can cause your RV water pump to pulsate.

Check the water pump pressure switch and diaphragm.

If you have a pulsating water pump, the problem could be that the pressure switch is not working properly or that there's a problem with its diaphragm. The pressure switch controls how much water flows into your home by regulating how much air is allowed to enter into it through an air valve on top of your tank. If this isn't functioning properly, then you may experience some problems with getting enough water flow during showers or flushing toilets.

The second thing to check if your RV has a pulsating water pump would be its diaphragm. This rubber seal keeps out dirt and debris while allowing proper amounts of liquid in between these two parts inside your tank so they can work together effectively without causing any damage due to excessive wear or friction from rough surfaces rubbing against each other too hard over time (which happens eventually).

The cause of a pulsating pump is usually undetected problems with the pump itself or with the piping that connects it to a pressure switch and controlling relay valve.

If your pump is pulsating, there are a number of possible causes. The most common reason for this symptom is inadequate water pressure to the system. This can occur because:

The pump is not getting enough water to operate properly (e.g., a broken meter or valve in the intake piping)

The pump isn't getting enough power from the battery/generator (e.g., if you used up too much energy during an overnight stay at a campsite with no hookups)

A solenoid valve has failed and won't open properly; this will cause reduced flow through the system when it should be normal or high flow—depending on whether it was previously opened by the RV's control panel or actuated automatically when needed during use in motion (as will happen during an emergency situation).

We've seen that there are a number of causes for RV water pump pulsation, but the most common cause is an undetected problem with the pump itself or its piping. If you're having problems with your RV's water supply, it would be a good idea to call in an expert who can help diagnose and fix the problem.

How to Fix an RV Water Pump Seal

Fixing a broken seal on an RV water pump is fairly simple. This can be done by replacing the seal, but you will need to know how to shut off the water supply so that you can work on it.

Shut off the water supply:

In most cases, shutting off the water supply is as simple as turning off a valve or flipping a switch on your RV's water system. Some systems have an electric switch, while others use a manual lever control valve. If you have any questions about where to find these valves inside your RV, look carefully for them before attempting to shut them off.

The first thing to do is check the leak. If it's a small drip, you might just be able to fix it with some sealant. But if you hear a loud gurgling sound coming from your water pump, then chances are that the seal has failed and needs to be replaced.

The second option is to replace the entire pump assembly, which may be more cost-effective depending on how old your RV is and what kind of damage has been done to it.

If you aren't sure which option is best for your particular situation, talk with a professional about what they recommend.