Pressure Washer Soap Injector Not Working

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You have some free time, and you want to wash your car with your reliable pressure washer that you have been using for a while now. You notice that everything is running smoothly, and the water is flowing out of the hose at the right pressure. But just when you think that soap washing your car might be a good idea to clean the dust off, you notice that its only water that comes out and no trace of a detergent at all. If you aren’t into DIY maintenance stuff and don’t exactly know where to start from, then you’ve come to the right place. This article provides you with all the troubleshooting steps and the necessary procedures detailed in headings and bullets that will help you resolve your problem.

Pressure washer soap injector not working, what should you do:

  1. Inspect the nozzle type
  2. Check for blockages

Some additional causes include:

  1. Worn out components
  2. High inlet water supply
Pressure Washer Soap Injector Not Working 1
(CC BY 2.0) by Wonderlane

If a soap injector isn’t working, the most common cause is the high back pressure build up in the nozzle or blockages in the chemical injector nozzles. We have listed each of the troubleshooting steps with their procedures individually:

If you don’t know about the pressure washer components and the necessary maintenance steps, you don’t need to worry. We have broken down the instructions into user-friendly and straightforward steps.

Soap Injector Working:

Before troubleshooting a pressure washer soap injector, it is mandatory to understand precisely how a soap/chemical injector works. It’s a device that constricts or narrows down a flowing stream of water through the nozzle so that the soap water is drawn from its container through suction.

The key is that the narrow stream increases the water’s flowing velocity, ultimately decreasing its pressure and hence pulling the soap towards the vacuum suction. It should be noted that the pressure within the injector is not too high because, in that case, no suction of the chemical would occur. Instead, the water will flow from the stream into the detergent container.

A valve further controls the drawing of chemicals from the injector. If the flowing water stream’s pressure is high, then the valve limits the fluid flow back towards the soap container.

Steps to Fix Pressure Washer Soap Injector:

Now that you know a soap injector’s working principle, it will be easier for you to understand the causes behind the soap injector not working correctly. We shall list down several troubleshooting steps that you should try doing, and that will help you pinpoint the cause and apply the solution to solve the problem.

1. Inspect the nozzle type:

If your soap injector does not seem to work, then it is highly likely that the buildup of the backpressure of the flowing stream of water is relatively high, which prevents the chemical’s suction. To check this, you should first inspect your nozzle and check if it’s high pressure or a low-pressure nozzle.

– Solution: Using a low-pressure nozzle:

If your pressure washer uses a high-pressure nozzle, it is the probable cause of your injector problems. You should go through your user’s manual and determine the prescribed nozzles for given pressure types. Generally, high-pressure nozzles are not suitable to operate the chemical siphon/injector. So, you should switch towards using a low-pressure nozzle for your device and see if it works.

2. Check for Blockages:

Another frequent problem that you may witness with the chemical injector will be blockages at the nozzle or valve area. This is usually caused by debris build up in the chemical injector tube. This prevents the siphoning of the chemicals.

– Solution: Cleaning the dirt:

This problem can be resolved by plugging out the debris from the affected area by checking the tube, nozzle, and valve to see which area is affected. As a preventative measure, you can install a chemical filter on the tube to prevent clogging. This filter will not allow the passage of foreign dirt particles in the tube, and thus no clogging will occur.

Additional Causes:

1.      Worn out components:

Clogging or blockage in the tubes is caused by dirt and the components that are worn out and need to be replaced. That does not mean that you should install a new chemical injection kit. However, it means that maybe other parts might have a problem. Hence it would be best if you troubleshoot to identify the problematic part.

– Solution: Trial and error:

  1. The right way of solving the problem is to remove the hose from the pump and check if the chemical kit is working correctly.
    1. If the detergent chemicals are drawn out, then this indicates that the removed component was faulty. If it doesn’t, keep removing other components with the engine still running until detergent siphoning occurs.
    1. Afterward, keep adding all the removed parts such as soap injector, nozzle, valve, etc.

2.      Inlet Pressure too high:

If the inlet water jet comes at very high pressure, then the chemical injector will not be working. There are two causes for a high-pressure water jet. The first cause is the use of a high-pressure nozzle. We already discussed its solution above. The second reason might be that the water supply valve opened at its due to which the water pressure is significantly high, causing the injector not to draw the detergent.

– Solution: Adjust the valve position:

Keep changing the water supply’s valve position so that the water pressure varies and reaches a point where the detergent is drawn along with the supply from the hose.

Related Questions:

1. How do you use a pressure washer soap injector?

To use a soap injector on your pressure washer, follow these steps:

Step 1: Fluid inspection:

The soap injectors that you use are in-built or external. In both cases, the first step is the fluid inspection.

Step 2: Ensure the correct pressure:

Ensure that the water hose delivers water at the right pressure, and no leaks occur.

Step 3: Check the detergent hose:

Then, check the chemical/detergent hose and remove the inside dirt/blockages (if any).

Step 4: Check the soap solution:

Then, you need to check your soap solution. As a general guideline, the appropriate composition of the solution is 1/3rd soap and 2/3rd water.

Step 5: Install the soap nozzle:

Once you have the hose placed into the soap solution, you should install the soap nozzle or the soaper tip onto your wand.

Step 6: Start cleaning:

When you start your pump and open the water supply valve, an atomized soap solution comes at high pressure, which you can use to clean your vehicle or driveway.

2. How do downstream chemical injectors work?

Downstream chemical injectors work by narrowing or restricting the flow of water in a tube. This ultimately reduces the pressure and sucks out the soap solution, mixed with the flowing stream of water. This effect is called the venturi’s effect. Usually, the orifice size is made small since it reduces the pressure significantly and generates a vacuum. Generally, high pressure or absence of vacuum is the number one cause of not working on chemical injectors.

3. Can we put bleach in our pressure washer?

Bleach is generally used for killing mold and mildew. But If you’re looking to eliminate mold growing on your driveway or sidewalk by spraying bleach from a pressure washer, then we recommend that you should never do that.

  • Damage the pump’s seal: Bleach can damage the pump’s seals and essentially lead to oil and water leakages that will make your pressure washer highly ineffective and add to your maintenance costs.
  • Toxicity: Bleach is a toxic chemical, and spraying bleach in the air has environmental and health hazards for plants, animals, and human beings.
  • Scrubbing than spraying: If, in any case, you want to use bleach, then you shouldn’t spray. Instead, try scrubbing it onto the surface and let it sit for some time. In this way, the chemicals won’t be released in the air.
  • Pressure washer brush: We recommend using a pressure washer brush for scrubbing the bleach on the surface.

4. What chemicals do pressure washers use?

The choice of chemicals used depends on the commercial or domestic use of the pressure washer and its purpose. It all depends on what kind of dirt is to be removed. The cleaning materials are different in different areas. What works in one place may not be suitable elsewhere:

  • Oxalic acid – used in rust removal and other cleaning applications
  • Citric acid – used in removing stains or cleaning driveways
  • Sodium hypochlorite – used for disinfection and stain removal
  • Sodium hydroxide – used on glass and steel for dissolving fats and oils
  • Ammonia – excellent for cleaning stainless steel and glass.
  • Potassium hydroxide – used in soap making

Final Remarks:

Hence, we can conclude that to resolve problems pertaining to chemical injection, one must first understand the working principles of these devices. The causes are not as complex, and the troubleshooting steps are also easy. However, in any case, maintenance is what needs to be prioritized. As a golden rule, we should always remember to keep the hoses and nozzles of our washer clean and prevent the buildup of dirt of dust particles. Taking care of the machine will undoubtedly result in the machine taking care of us.