How to Unclog a Pressure Washer

It’s pool cleaning day! Your weekend plans got cancelled so you decided to pressure wash the pool. Summer isn’t over yet and a pool party does sound good. A look at the pool tells you that it will be a long day. You drag out the pressure washer from your garage and connect the hose to the tap. Your plan is to clean the surface tiles today, allow the pool to empty overnight and then deep clean the next day.
With the hose in hand, finger on the trigger and the nozzle trained… you press but nothing happens. There’s a sputtering sound, a few drops of water dribble out the nozzle and then the pressure washer goes silent. You turn off the tap and check the hose but don’t see anything there. Once again, after connecting the hose, you assume the position and press the trigger but… NOTHING.
What’s going on?
Haven’t you figured it out yet? Your water pressure is clogged! The good news is ― you can easily clean it with just a pin or paper clip.
The following guide on how to unclog a pressure washer covers everything from causes to problems, solutions and steps to cleaning the clog:

What Causes a Pressure Washer to Clog?
Debris: The most obvious cause behind a pressure washer clog is debris. Even though the nozzle is quite small and there’s a water filter to prevent debris from getting in, tiny particles get stuck to the surface and harden over time. This affects your machine’s performance.
Caking: The worn out materials, both inside and outside the machine, break off into tiny pieces and clog the nozzle.
Wear and Tear: Broken rubber seals that disintegrate and block the hose.
Wrong Detergent: High powered detergents can cause corrosion and erosion in various parts of the machine. The resulting mess is what clogs the nozzle.
Dirty Water: If your tap water is not clean, the dirt can deposit on the nozzles and clog it from the inside.
When a pressure washer clogs, either of the two things happens: the pressure gets low or the machine doesn’t work at all. The following chart will explain all the water pressure problems and their solutions:
Water Pressure Problems | ||
Problem | Cause | Solution |
Low Pressure | Incorrect nozzle | Check if the right pressure is used for the right nozzle |
Insufficient water supply through the inlet | Make sure the garden hose is big enough to match the pressure, ensure the tap is turned on all the way and unkink the garden hose | |
Blocked water filter | Remove the hose and remove debris | |
No Pressure | Damaged unloader valve | Tighten the screw and check for damaged seals |
Damaged inlet valve | Disassemble the pump and clean the inlet parts | |
Spiking Pressure | Unloader valve not calibrated properly | Check the manual and adjust the pressure |
Pressure Washer Not Cleaning the Surface | Wrong nozzle | Switch nozzle and pick one that offers higher pressure |
Pressure Drops Immediately After Starting | Unloader valve issues | Remove unloader and repair the valve |
Nozzle blocked | Use a pin to clear the clogs | |
Pulsing Pressure (Low Then High) | Faulty pump | Replace the pump |
Damaged inlet | Disassemble the pump and replace the inlet manifold | |
Obscured nozzle | Use a pin to clear the clogs and vinegar to flush the debris | |
Pump sucking air | Keep the water tap on but turn off the machine. Now squeeze trigger to release air |

Here are 2 Ways to Unclog Your Pressure Washer
Now that you know what’s causing the clog, let’s take a look at how to clear it:
1. Clean the Nozzle With a Pin
Equipment Needed: A Long Steel Wire or a Straightened Paper Clip
Step 1 – Remove the Nozzle
It’s important to remove the nozzle because if you use the pin to poke the holes while it’s attached to the hose, you might clog it from the main point of connection.
Step 2 – Poke the Holes
Hold the nozzle sideways and poke the holes one by one. When the pin comes out the other end, use a cloth to wipe off any deposits.
Step 3 – Rinse the Nozzle
Hold the nozzle underneath a tap and turn on the water. Let the deposits wash out. Insert the pin a few more times to make sure that there are no more clogs.
Step 4 –Reattach the Nozzle
Once the nozzle is attached to the hose, turn on the machine. Now adjust the water pressure and make sure that the water is coming out right.

2. Clean the Nozzle With White Vinegar
Vinegar is one of those trusty household items that can help clean just about anything. You can even use it on and in your pressure washer. It’s a greener choice and with the addition of a few drops of essential oil, you can leave the place smelling really good.
When calcium deposits and dirt harden inside or outside a nozzle, scraping them does not work well. This is where vinegar comes in. Simply fill a bowl with white vinegar and place the nozzle in it for a few minutes. The acidic properties of vinegar react with calcium, dirt and grease, and dissolve everything it comes in contact with.
Vinegar is not harmful to you in any way. However, when using it for your pressure washer, stick to white vinegar. Plus, don’t mix it with detergents or any other chemicals when adding it into the machine.

Our Final Thoughts
And that concludes our seminar on how to unclog a pressure washer! We have mentioned every possible cause of a pressure washer clogging, along with its solution. Better save this guide to refer to next time your pressure washer doesn’t work.
If all the above mentioned tips and tricks don’t work then your pressure washer is probably too old and broken. No need to buy another one. It’s not like you are cleaning your pool or pavement every day. We recommend renting it so that you don’t have to go through this hassle.