When your air compressor doesn’t turn off, it feels horrible, right? Don’t be upset. Because you are not alone in facing this issue since it has become our website’s most frequently asked troubleshooting question.

Therefore, the reason for this problem can be different depending on the situation. Like defective pressure switches, faulty tank valves or seals, motor problems, dirty air filters, and many more.

Here, I have compiled a list of the typical causes for your air compressor not turning off. And included reader queries and solutions to resolve issues with compressors.

1. Issues with the Pressure Switch

Issues with the Pressure Switch

The pressure switch can be defective over time which is a risky one. The compressor relies on the pressure switch to detect when it has attained the pressure cut-off portal. And this causes the motor won’t shut down and prevent further air compressing until the pressure level drops to the cut-on point.

If the switch has failed, the machine will keep operating and increasing pressure. As far as the Pressure Release Valve (PRV) activates and releases air, reducing pressure. However, this will not prevent the compressor from running and may sustain damage if allowed to continue running.


If your compressor operates beyond its usual cut-off point, do not use it until it’s repaired. The solution is to replace or change the switch to a new one. But finding the original parts for air compressors can be difficult. Fortunately, you can use a substitute with a different pressure switch as long as certain conditions are met.

2. Defective Pressure Release Valve

Defective Pressure Release Valve

Earlier, I talked about the pressure release valve (PRV) being unable to release air when it builds pressure up. This is not the only issue that can occur with the PRV. In reality, if your air compressor continues to run, a defective PRV can release air before the maximum pressure limit is reached.

If the PRV is releasing air when it should not, your compressor may continue to operate in an attempt. To compensate for the air that is being lost through the valve.


Repairing the faulty pressure release valve on air compressors is relatively simple. You can change the damaged part with a new part compatible with your model. However, it is essential to depressurize the tank first and fix the compressor when unplugged or turned off.

3. Faulty Tank Check Valve or Seal

Faulty Tank Check Valve or Seal

The tank check valve of an air compressor is located between the tank and the pump. Its primary function is to stop the air from returning to the pump by ensuring that it only flows in one direction, which is toward the tank. The valve acts barrier that prevents the air from discharging out of the tank and returning to the pump.

When the check valve is malfunctioning, air may escape from the tank. And which can lead to the compressor’s inability to generate pressure and run continuously. In some cases, the leakage may occur because the connection between the check valve and the tank is not sealed correctly.


Replacing the check valve is an easy task. To do so, you must first release the pressure from the tank and make sure that the machine is unplugged and turned off. Next, you will need to detach the compressor pressure switch tube from the check valve. Then also, cut off the outlet tube. This will let you discard the old check valve from the compressor tank and install the new one.

4. Wear Out Intake Valve

Wear Out Intake Valve

The location where the air compressor draws in air for compression is known as the intake valve. This valve is a crucial system component, but it can become worn out over time. When this occurs, the air compressor will struggle to draw enough air to generate sufficient pressure for your intended task.

If the intake valve is not functioning correctly, it can result in the air compressor continuously running. It is beneficial that specific compressors feature multiple inlet valves.


The majority of owner’s manuals provide guidelines on how to replace them. So it is recommended to refer to your manual for instructions on replacing the inlet valves specific to your particular model.

5. Leaky Gaskets

Leaky Gaskets

Another reason your compressor keeps running non-stop can be a faulty gasket causing a leak. Occasionally, the compressor may accumulate pressure until it reaches a specific level. Such as 50 or 60 psi, but it won’t increase any further and will continue running.

It is possible there could be a leak in various parts, and it’s difficult to confirm if the gasket is faulty just by inspecting the compressor externally. Usually, you’ll need to disassemble the compressor to identify whether a leaky gasket is a leading cause.


You’ll need to remove the pump housing to fix this issue, which will require some time. And then check you have the correct replacement gasket. However, if you’re uncertain that this is the root cause, you might disassemble it unnecessarily. Hence, examining other potential causes is necessary before pulling apart your pump.

6. Rings and Seals

Rings and Seals

Your compressor may continue running if the air is escaping from other locations. These locations include seals and o-rings, which are prone to wear down with time.

Identifying a leak in an internal ring or seal can be challenging and typically involves a process of removal. Nonetheless, you can apply the soap-and-water technique to check for leaks around external connections or o-rings.


Repairing a leaking seal or ring relies on the compressor’s type and the leak’s location. To illustrate, fixing a tube seal leak would require taking apart the pump again, replacing the seal, and then reassembling it.

If you decide to disassemble the pump, replacing any gaskets and other parts prone to cause leaks will be best.

7. Motor Problems

Motor Problems

If the pressure within your tank increases but doesn’t reach the pre-determined cutout pressure, your compressor motor persists in operating. There’s probably an issue with the compressor motor or the pump itself.


The following action is to remove the air inlet filter and verify if it’s not emitting any air. If you notice air coming out of your air compressor’s air intake, then you should replace the air intake valve. To check this, remove the line connecting with a pump and tank, and use your hand to obstruct the airflow from the pump while it’s functioning.

8. Dirty Filters

Dirty Filters

One potential explanation for why your air compressor is not shutting down could be the filters in your compressed air system. It can become obstructed, which could impact the airflow.


To ensure this problem, you should examine all filters and replace those that have accumulated dirt or debris.

9. Inoperative Piston

Inoperative Piston

This problem is uncommon and typically affects individuals who possess outdated air compressors. Several issues can arise when air compressors are improperly maintained, including a faulty piston. 

The piston is located in the air pump, compressing the air. When the piston becomes worn down or the rings break, it can block the pressure from building correctly. Consequently, the compressor will continue functioning but struggle to reach the maximum pressure. As a result of this problem, it appears that the compressor does not turn off.


In order to repair a faulty piston, either the piston itself or its rings must be replaced. Once the new piston is installed, it will generate more pressure and reaches its maximum level before stopping.

A lot of people have an air compressor that operates using a belt. But they’re experiencing an issue where the tool doesn’t turn off even after being switched on. This problem is likely caused by a loose belt, which prevents the wheel pulley from rotating the air pump effectively. The belt slips from the edges and fails to produce the necessary cutout pressure when the belt is loose. And this can cause the compressor to continue working.

10. Loose Belt

Loose Belt

A lot of people have an air compressor that operates using a belt. But they’re experiencing an issue where the tool doesn’t turn off even after being switched on. This problem is likely caused by a loose belt, which prevents the wheel pulley from rotating the air pump effectively. The belt slips from the edges and fails to produce the necessary cutout pressure when the belt is loose. And this can cause the compressor to continue working.


To resolve the issue, you need to change the belt. You can refer to the tool’s owner manual to determine the belt size needed. After fitting the new belt, the compressor will work adequately and automatically switch off once it reaches the maximum pressure rating.

11. Damage Air Gauges

Damage Air Gauges

An air compressor that fails to turn off can be caused by a frequently occurring issue, a malfunctioning air pressure gauge. While in operation, the gauge measuring pressure will continue to increase until it reaches the point at which the compressor should stop.


If the air gauge on the tank fails to increase or only increases slightly and then stops. Despite the compressor continuing to operate, the gauge is probably defective. You can switch off the compressor to determine if this is the case. And then listen for any indications of air leaks emanating from the gauge or its connections.

Final Words

When your compressor keeps running continuously often, it’s typically due to a problem with the pressure switch. Still, there can be other causes for this issue. And to identify the leading cause, you must analyze the problem with the tricks as mentioned above. Some resolve causes easily, but others may require more significant efforts.

Remember to avoid using your compressor if it keeps running without stopping until you have fixed it. Operating it under such conditions can cause damage to the compressor, and it could even pose a safety risk.

Hopefully, the information given will help you determine why your compressor doesn’t turn off.


What causes the air compressor to stay running?

There are several possible causes for an air compressor running too frequently, including leaks in the piping or fittings and malfunctions in the mechanical. Or electrical components of the compressor and incorrect piping connections between the compressor and sprinkler system.

How do you turn off an air compressor yourself?

First, ensure all tools and attachments are disconnected from the compressor to turn off the air compressor. Then, switch off the power supply or unplug the compressor from the electrical outlet. Finally, wait for the compressor to stop running entirely and for the motor to come to a complete stop before performing any maintenance or repairs.

Why won’t my compressor reach cut-off pressure?

A faulty reed valve is often responsible for a reciprocating compressor’s failure to attain adequate pressure. This valve can allow air to escape either through the air inlet on single-stage models or via the intercooler safety valve on two-stage piston compressors. Rather than routing it through the intercooler, second-stage piston, and discharge as intended.

What happens if an air compressor runs continuously?

Air compressors with a 100% duty cycle are the only ones capable of running continuously at the stated pressure and flow rate. If an air compressor is operated beyond its duty cycle limit, it can result in premature deterioration. And it will increase maintenance expenses and, in severe cases, equipment failure that can cause production to halt.

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