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Fix low pressure on a pressure washer? Tips from pros

When using any machine, it will cause some problems for you and in case of pressure washer, the most common problem is the loss of high pressure. Every pressure washer gets low on pressure with time and almost all of us may have faced this problem at least once in our life. However, there is no single reason behind this low pressure of the pressure washer.

Generally, the first step for fixing the low pressure of your pressure washer is changing its oil and cleaning the filter. And if the pressure of your washer has still not increased then check the water supply hose and adjust the unloader valve to your desired pressure. Most of the times, the nozzle of the pressure washer is torn out that causes the low pressure on a pressure washer. You can fix this problem by replacing the nozzle of your pressure washer.

Through this article, you will learn about different factors that could be the reason for the low pressure of your pressure washer and we will also provide you with the solution to fix the low pressure on your pressure washer.

How do you fix low pressure on a pressure washer?

The reason for using the pressure washer to clean the exterior parts of your house is that it produces more amount of pressure than the normal pipe attached to the tap. But still a lot number of pressure washer users complain about their washer producing low or very minimum pressure. There can be many reasons for this problem and in order to fix them, we have come up with some solutions that can be very helpful for you to fix the low pressure on your pressure washer.

Solution 1: Maintenance of your pressure washer 

The first solution to fix the low amount of pressure on your pressure washer is to properly maintain it from time to time. Many people simply just use their pressure washers to clean different areas of their house and they do not give proper attention its maintenance. When these pressure washers runs on a high pressure to clean the areas like concrete then they use more power than the normal that results in the consumption of more oil.

So in order to fix the low pressure of your washer, you should give proper attention to the maintenance of your washer and change its oil after regular interval of time. Also the nozzle and filter of your washer catches a lot of dust particles during cleaning and it causes hindrance for the pressure washer to maintain its high pressure. Therefore, you must clean the nozzle and filter of your washer before or after using it for cleaning the dust.

Solution 2: Fixing the hose

Now if your pressure washer is still producing low pressure after changing the oil and cleaning the nozzle then you should move forward and check the hose of the water supply going in to the machine. In case of most pressure washers, it is essential to supply them with at least of 1 gallon of water per minute.

 According to most experts, the recommended diameter of the supply hose should be ¾ inches to fix the low pressure of your pressure washer. If the pressure of the washer is still low at the given ¾ inch diameter of the hose then check for any blockage in your hose. Loosen the hose from the inlet valve of the pressure washer and clear the dust and debris from the inside of filter that could be the reason for low pressure of water from your pressure washer.

Solution 3: Adjust the unloader valve

The main function of unloader valve is to divert the water flow from the pump towards the bypass. This unloader valve can also be used to fix the low pressure of water coming out of the nozzle of the pressure washer.

In order to do so, first check the nozzle of the pressure washer and if it is torn out, replace it before adjusting the unloader valve. Then adjust the unloader valve in small steps to increase the pressure of the washer. Also connect the pressure gauge when adjusting the unloader valve in order to prevent the pressure from getting too high. During the adjustment of the unloader valve, ensure that the machine is running and pull the trigger wand to allow the flow of water through the machine. Now if your machine is still producing a low amount of pressure after adjusting the unloader valve then your valve can be broken and in a need of replacement.

Solution 4: Replace the nozzle

Another solution to fix the low pressure of the pressure washing machine is by replacing the nozzle at the of trigger wand. Sometimes, nozzle at the end of trigger wand becomes worn that results in unusual spraying pattern of water. This worn out nozzle can also be the cause of low pressure of the pressure washing machine because of the holes in it that widens with time. Because as these holes widens, more water flows through the nozzle thus decreases the pressure of the water. Nozzles will wear over time with regular use, and will need to be replaced. It is recommended to have a number of nozzles on hand.  This allows you to easily change the nozzle if you see any decrease in pressure and test other nozzles to check if the pressure is decreased due to the nozzle or not.

Regardless of which pressure washer you choose, selecting the right nozzle is vital to fix the low pressure of the pre Nozzles determine the angle of the water stream emerging out of the pressure washer. Pressure washer nozzles are universally color-coded. The color of the nozzle’s tip determines the angle of the water stream. Generally, pressure washer nozzles come in four different colors.

Red nozzles:

A nozzle with a red tip represents the narrowest angle which is 0 degrees. This nozzle creates a water stream with the high pressure. Using a red nozzle with your pressure washer can fix the low water pressure of the machine. A red-tip nozzle can do a lot of damage and must be used with care. It is recommended that the red-tip nozzle should not be used up close on any surface.

– Yellow nozzles:

The yellow tip nozzle creates a water stream at an angle of 15 degrees. It is recommended to be used when you want to clean concrete surfaces.

Green nozzles:

Green tip nozzles sprays water at the surface at an angle of 25 degrees. This tip can be used to pressure wash your car, clean mildew accumulated on patio or deck or for any other household pressure washing.

– White nozzles:

A Whitetip nozzle is used to clean windows or sidings with little dirt. It produces a water spray with 40 degrees. It is the most user-friendly nozzle and causes no damage to the surfaces.

– Black nozzles:

Blacktip nozzle produces a water stream with 65 degree angle. It is the gentlest nozzle and does not remove stains or dust. It is used to just wet a surface.

Why is my pressure washer low on pressure?

Many factors affect the pressure of your pressure washer and the most important factors are the worn out nozzle and dirt blockages. Other than these factors, a loose or slipping belt and air leakage also causes the pressure washer low on pressure. For the electrical pressure washer, motor malfunction can be the reason behind the low pressure of water and for the gas pressure washer, deficiency of oil could be the factor for the low pressure of the pressure washer.

With time, every pressure washer loses pressure and because of this reason you are unable to clean your surface effectively. Apart from the problems mentioned above, there can be many reason for your pressure washer being low on pressure and in the below section, we have provided you with the most common factors that could be the reason for the low pressure of your washer.

Factor 1: Worn nozzle

As explained earlier, the nozzle of your pressure washer worn out with time that reduces the pressure of the water coming out of it. So before using your pressure washer, check the nozzle and if it is worn out then replace it with the proper size and color.

Factor 2: Loose belt

Another important factor behind the low pressure of your pressure washer is that if the belt of your machine is loose or slipping then it results in the decrease in the pressure of water. You can fix this problem by tightening or replacing the belt.

Factor 3: Air leakage

This could be confusing to you but it is quite simple. It means that there might be some air leakage though the inner plumbing of your pressure washer that decreases the pressure of the air inside the machine. This high air pressure is very important to maintain the high pressure of the water and you can fix this problem by first disassembling your pressure washer, fixing the area through which the air is escaping and then assembling the pressure washer.

Factor 4: Dirt

Sometimes, after using the pressure washer for the number of times, a significant amount of dirt gets stuck inside the nozzle and clog it. Due to these reasons, your pressure washer runs on a very low pressure. This problem can be identified very easily because under these conditions, the spray pattern of water coming out of the nozzle will be uncontrolled and less water will be delivered to the surface.

You can fix this problem by simply cleaning the nozzle and of the nozzle is too torn out then replace it. Sometimes dirt also gets stuck in the wand that results in low water pressure so check the wand as well and if there is any leakage in the wand then seal that area or replace it.

Factor 5: Pressure pump

In most of the cases, pressure pump is the reason behind the low water pressure because with time, dirt and debris gather inside the inline filter that increases to a significant level after a couple of washing. So as a result, your pressure washer runs on a very low pressure. In order to get rid of this problem, clean the inline filter with the air blow and if your machine does not have any inline filter then make sure to install one.

Factor 5: Motor malfunction

Unlike the gas pressure washer, electric washer runs on a motor that is the key source of producing power. With the use of this power, the pump works and generate a high pressure of water. If your motor malfunction, the pressure washer ends up losing the high pressure of water. So make sure that the motor of your pressure washer is working fine and in order to do so, push the throttle couple of times and if your pressure washer produces high and low pressure then your motor is fine.

Electric pressure washers are more convenient than gas pressure washers because they do not require any engine oil to operate. They require very little maintenance as compared to gas pressure washers. Electric pressure washers do not produce gas fumes or any other harmful emissions and they can be easily used for indoor applications.

However, electric pressure washers do not provide high power like gas pressure washers. Large and extremely dirty areas cannot be cleaned quickly and effectively with electric pressure washers. An electric pressure washer takes much longer than a gas pressure washer to clean large areas and there is also a great difference between the cleaning results of the two washers. Electric pressure washers are not portable because they have a cord and require a power outlet to operate.

Factor 6: Gasoline engine of the gas pressure washer

The problem behind your gas pressure washers low on pressure is that they consist of a gasoline engine which requires proper maintenance. You have to change the oil in the engine. Moreover, you have to add fuel additives if you want to store the machine for a long period of time.

Gas pressure washers provide more powerful cleaning than electric power washers. They provide higher PSI (Pound per Square Inch) and GPM (Gallons per Minute). This means that the gas pressure washers clean the surfaces more quickly and effectively. They are generally used to clean hard surfaces like concrete. Gas pressure washers provide a wide range of PSI and GPM levels which give you more options to adjust the pressure of the washer. You can use gas pressure washers easily as these pressure washers are cordless due to the fact that they are powered by gasoline.