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Is Your Pressure Washer Losing Pressure?

One of the joys of home or property ownership is that when your property gets dirty, then you are the one responsible for cleaning it. Rather than spend money on professional cleaning services, you decide to invest in a pressure washer and do the cleaning yourself. However, you have recently noticed that the “pressure” is conspicuously absent from your pressure washer.

Is your pressure washer losing pressure? There are myriad reasons that your pressure washer could be losing pressure, with some being extremely simple explanations easily troubleshot by the owner. A simple run through common issues can often get your pressure washer spraying at full force in no time.

While many pressure issues in your pressure washer are often easily explained, neglect or other forms of misuse can lead to more serious mechanical issues. If this is the case, a reduction in pressure is most likely to be permanent, and you will need to see a professional for a repair or replace your pressure washer altogether. But first, let’s see if it’s something you can take care of right at home.

How Does a Pressure Washer Work?

Many of you are probably familiar with using a garden hose to spray out a dirty carport or getting a push broom to sweep down a patio that has gotten caked with dust and other debris.

Sometimes, though, the area that you need to clean is just too dirty for either of these methods to work effectively, and you simply do not have time to go around to every nook and cranny with a bucket of cleaning supplies and Brillo pad to scrub all problem areas clean.

A pressure washer is part air compressor, part garden hose. Typical pressure washers come on wheels and look roughly like a push lawnmower. They will use either a gas-powered engine or electric motor to power a water pump.

The following steps should be used to ensure that your pressure washer works correctly, making it a super duty cleaning accessory that will provide maximum pressure over the longest lifespan:

  1. Place pressure washer on a flat surface – you always want to make sure your pressure washer is sitting level before attempting to start, as well as check for any debris you may notice on the body or in the water strainer.
  2. Attach pressure washer to a garden hose – this provides the water supply with which the pressure washer will use to clean, so make sure the hose is securely connected to both the pressure washer’s intake port and the spigot you will be using.
  3. Connect the high-pressure hose to the water outlet – this is a reinforced hose that will be able to withstand the force of the pressurized water coming from the water pump. Also, attach the release nozzle you want to use for your cleaning project to the opposite end of the high-pressure hose.
  4. Turn on water supply – it is important to flush any excess air that is sitting in the hoses prior to starting the pressure washer. This is easily accomplished by turning on the water supply and holding the trigger on the release nozzle, allowing regular water to flush out any sitting air.
  5. Turn on pressure washer – once both hoses are securely connected to the pressure washer, and all excess air has been flushed, turn on your pressure washer. This may be in the form of a pull handle starter for gas engines, similar to most push lawn mowers, or via a push-button for electric motor models.

Your pressure washer is now ready to get work, capable of blasting away debris at many times the force of a regular garden hose.

Copyright protected content owner: ReadyToDIY.com and was initially posted on April 16, 2020.

What if the Water Pressure Gets Weak?

There are a couple of important terms on which your pressure washer is rated, giving an indicator of how much force it is capable of supplying:

  • Pounds per square inch (PSI) – this is the water pressure measured at output. This can range from as little as 1,500 psi for smaller models to 3,000 psi for industrial pressure washers meant to tackle major grime. Considering that car tires hold about 32 psi, you can see how much pressure these appliances are capable of thrusting.
  • Gallons per minute (GPM) – this measures the amount of water delivered to the spray gun. Most pressure washers operate most effectively on 3.0 GPM, but this number may differ by .5 GPM in either direction, depending on the model.

If you start to notice that your pressure washer is not spraying water with the force you have come to expect, then one or both of these figures could be out of whack. There are several things you will want to look into to get these ratings back where they need to be.

No Nozzle Attached

In order for a pressure washer to function properly, it must have a nozzle attached to the end of the high-pressure hose. Without a nozzle to direct the water, it will simply come out similar to garden hose pressure.

Therefore, the first place to start is to check and make sure that there is a nozzle attached to the end of the high-pressure hose. While this seems like an obvious step, the nozzle tips are often small and inconspicuous, so if you are new to pressure washers, the explanation for your low pressure may be easily solved by properly attaching the nozzle.

If the nozzle is secure and the pressure is still low, then you are likely looking at a blockage somewhere in the water transport process.

Clogs or Leaks in Hoses

Using the steps provided earlier in this article, you will know that there are two hoses connected to the pressure washer: a garden hose that runs the water from the supply to the pressure washer, and a high-pressure hose that directs pressurized water out of the pressure washer for cleaning.

Before turning the pressure washer on, you are supposed to flush excess air from these hoses by running regular water through the system. 

If you attempt to do this and no water comes out when you hold the trigger on the release nozzle, then you are dealing with a clog in one of your hoses.

There are several manners in which you can potentially clear the clog in your hoses and get your pressure washer back to full pressure in no time:

  • Disconnect the garden hose from pressure washer – you will want to start by checking to see if the clog is coming from the water supply hose. If no water is coming out of the garden hose when disconnected from the pressure washer, work to locate the clog and get it cleared before reattaching the garden hose to the pressure washer.
  • Check the nozzle tip – if the water supply is not clogged, the most likely blockage is coming at the tip of the nozzle itself. This can be particularly true if your pressure washer has been sitting for a long time and had some debris build up in its components. To check this, take the following steps:
    • Remove the nozzle tip from the end of the pressurized hose – this is a small plastic accessory and should easily pop off with a gentle pull on the end of the nozzle. You may need to work it a little bit harder to remove it if the nozzle is particularly dirty, so just be patient and do not use excessive force.
    • Hold the nozzle tip up in the light – if the nozzle tip is clean, there should be a small opening, about the size of a pinhead, in the middle of the tip that allows light to pass through. If you cannot see through this hole, then this is causing your pressure washer not to fire.
    • Clean the nozzle tip – with a regular garden hose, spray directly on the nozzle tip to remove the blockage. If the tip remains blocked, you may need to let it soak  in some water for a few minutes and get a pin or small wire to run through and remove the stuck debris.
    • Reattach attach the nozzle tip and test again – once the nozzle tip is cleared of any stuck debris, reattach it to the nozzle and run regular water through the system. You should get a weak stream of water that will clear the hoses of any sitting air, making your pressure washer ready for action .

Low pressure due to a leak in the hose will be easy to spot. With the spigot on and the pressure washer off, check to make sure that there is no water spraying from areas other than nozzle once the nozzle release is activated.

Copyright article owner is ReadyToDiy.com for this article. This post was first published on April 16, 2020.

If there is water squirting out of places it should not be, try to resecure your connections, reinforce the leak with a heavy-duty hose tape, or simply replace the hose altogether if the damage appears to be too severe.

Blockages at the Ports

If you are sure that there are no clogs or leaks in the hoses, then there is a chance that the low pressure is being caused by a blockage at either the water input or output port.

These ports will be very conspicuous on the pressure washer, with both being located very close together at the head of the machine. Carefully unscrew these ports from the pressure washer for closer inspection. Similar to the process for checking the nozzle tip, check to see if any light is passing through the ports. If not, you have a blockage.

Using a small screwdriver or thin wire, knock away any stuck dirt, rust, or other debris that may be impeding the flow of water to or from the pressure washer. Once clear, carefully reattach the ports to the pressure washer, making sure that all components go back in the same spot from where they came.

Worn Nozzle Tip

If the nozzle is properly attached and that there are no blockages in the hoses, ports, or nozzle tip, then you may very well be dealing with a worn nozzle tip.

Nozzle tips are designed to have extremely small openings to allow a very small amount of pressurized water to release when triggered. Because they spend so much time containing and releasing high-pressure water, it is only natural that they wear, causing the release opening to expand over time, which will lead to a reduction in pressure.

Compound this with the fact that most people have a favorite nozzle that they use time and again, and this small tip is likely to endure some wear and tear. Simply switch out your favorite tip with one of the other options that come with your pressure washer and take note of any changes in pressure.

If a worn nozzle tip is the cause of your low pressure, take a trip to a home improvement store and see if there are any replacement options that are the same size as your favorite that has become worn.

Why Do Pressure Washer Pumps Fail?

Unfortunately, the simple do-it-yourself explanations listed above do not account for 100 percent of the low-pressure scenarios in your pressure washer. If you have troubleshot all of the scenarios in this article and are still noticing weak pressure coming from your pressure washer, you are probably dealing with a failing water pump.

The water pump is the heart and soul of the pressure washer. Without it, the hoses, nozzles, and other components of the pressure washer are essentially decorations. The water pump moves normal water from the input source, mixes it with compressed air, and delivers it to the water outlet to be sprayed at extremely high pressures.

While the water pump in your pressure washer performs a small miracle and allows you to clean in ways you could have never accomplished with a regular garden hose, it is not infallible. As with all things mechanical, there is a chance that it stops functioning properly and needs to be replaced at some point in the life of your pressure washer.

There are a few simple reasons why the water pump in your pressure washer may fail:

  • Old – just as water pumps in cars go bad after years and miles of pumping coolant to the vehicle’s engine, water pumps in pressure washers can go bad after many years of use.
  • Neglect and abuse – there are many ways you could potentially abuse a pressure washer’s water pump, from keeping it exposed to extremely high temperatures, not securing it properly when transporting to new locations, or running dirty water through it.
  • Faulty – while unfortunate, there is a small chance that you simply got a “lemon” or a water pump that does not work the way it should. Your pressure washer should come with a warranty so if you notice failure in water pressure early in its life, check with the vendor and see what you can do about getting it serviced.

Obviously, there is not much you can do if you are unfortunate enough to get a faulty pump, and there is no time-reversal mechanism in which you can magically make your old water pump new again. However, issues of neglect and abuse are areas that you can definitely control, and there are a couple of specific issues pertaining to water pump care that you should keep in mind:

Cavitation

Cavitation is caused when insufficient water is introduced to your water pump. 

As mentioned earlier, pressure washers’ ability to supply water to the release outlet is measured in gallons per minute (GPM). If your pressure washer is rated at 3.0 GPM, then you need to be sure that you have your pressure washer connected to a source capable of supplying at least 3.0 GPM.

If the water source is supplying water at less than the recommended GPM, then your water pump will not be able to operate at full function. Over time, cavitation will occur, and your pump will “get used” to sending out lower pressure water.

Therefore, always make sure that your water source is capable of supplying the recommended GPM. A simple way to test this is to find a bucket the size of your pressure washer’s GPM rating and see if a regular garden hose can fill the bucket in a minute or less.

Overheating Due to Insufficient Bypass

When your pressure washer is on, water needs to be constantly circulating through the system.

With the water pump running but no cool water circulating through to cool the components, the internal temperature of the pressure washer can exceed 140°F in as little as 45 seconds. These high temperatures can cause the bearings of the water pump to rapidly deteriorate and will eventually lead to pump failure.

While most manufacturers recommend keeping water in bypass for no more than two minutes, it is best to keep it even shorter than that, circulating cool water through the pump every 30 to 45 seconds, maximum.

ReadyToDIY is the owner of this article. This post was published on April 16, 2020.

If you need to leave the cleaning area to take a phone call or run any other kind of errand, remember to turn your pressure washer off before doing so. This will prevent your water pump from overheating and ensure the extension of its useful life.