Why Is My Atlas Copco Compressor E-Stop Not Resetting?

On this page (6 sections)

1. Why is my Atlas Copco compressor E-stop not resetting?
2. What should you check before trying to reset it?
3. Can air pressure or a drained tank prevent a restart?
4. What if the emergency stop will not release?
5. Which products help with compressor-related tasks?
6. What should you do if the E-stop still will not reset?

An Atlas Copco compressor emergency stop that will not reset may still be latched, or the controller may be blocking a restart because a fault or safety condition remains active. Check the model-specific manual and displayed fault before trying again, and never bypass the stop circuit.

The button and the compressor's start controls may be separate steps. Releasing the emergency stop does not necessarily clear an alarm or command the machine to run.

Why is my Atlas Copco compressor E-stop not resetting?

The most likely causes are an engaged stop button, an active shutdown condition, or a control-circuit problem. The exact cause and reset sequence depend on the compressor model and controller.

An emergency stop should remain engaged until you can safely inspect the machine. If someone pressed it because of unusual noise, smoke, a leak, or another hazard, don't reset it until the cause has been addressed.

For a model-specific example, see Husky compressor noise.

Start with what you can see from a safe position:

• Check whether the emergency stop button is still physically engaged.
• Read the display for an alarm or fault code before clearing anything.
• Look for a separate start or reset control described in the manual.
• Check whether the machine is ready for operation, without opening electrical enclosures.

If the display is blank, the button is damaged, or the alarm returns after a reset, stop troubleshooting and contact qualified service.

What should you check before trying to reset it?

Identify the compressor model and controller, then use the instructions for that exact setup. Atlas Copco compressors can have different control layouts, so a reset method that applies to one machine may not apply to another.

Find the model information on the machine's identification plate, if you can reach it safely. Note any alarm text or code exactly as shown; that detail can help service staff diagnose the issue.

Keep clear of belts, fans, hot surfaces, and pressurized components. Don't remove covers, reach into the machine, or work on electrical parts unless you're qualified and following the required isolation procedure.

If the machine is stopped and the manual says the button has a manual release, follow that instruction without forcing it. A button that won't release smoothly may be damaged or jammed and needs inspection.

For the ordinary control sequence, see How To Reset Atlas Copco Air Compressor?. That reset guide does not replace the model-specific steps for an emergency stop or an active fault.

Does the Atlas Copco E-stop release but the compressor stay stopped?

Yes, the button can release while the controller still prevents a start. Check for a displayed alarm, an unmet operating condition, or a separate reset step in the manual.

Don't repeatedly press start or cycle the main power to see if the fault disappears. Repeated attempts can hide useful fault information and won't fix an underlying safety issue.

If the controller shows a fault you don't understand, write it down and check the machine's documentation or contact Atlas Copco service. Don't guess at a code or clear a fault without knowing what triggered it.

Can air pressure or a drained tank prevent a restart?

A pressure-related issue can affect whether some compressors start, but it does not explain every emergency-stop fault. Check the manual and controller indications before treating a restart problem as a tank-pressure problem.

If the machine stopped after air was drained, this guide to why a compressor will not restart when air is drained covers that separate symptom. Avoid opening drains or fittings while the machine is running or pressurized unless the manual instructs you to do so.

A compressor that hums or clicks without starting may have a different electrical or motor problem. See why an air compressor motor hums but does not start for that symptom.

What if the emergency stop will not release?

Leave the compressor stopped if the emergency stop will not release with the model's instructed action. Forcing the button or bridging its contacts can defeat a safety function and expose people to moving machinery or electrical hazards.

Check for an obvious obstruction only from outside the machine and without disassembling the button. If it appears damaged, stuck, or loose, arrange service rather than attempting a repair.

Don't use a bypass or substitute switch to get production running. A qualified technician can inspect the stop device, wiring, and controller using the appropriate isolation procedure.

When is the fault beyond a routine reset?

Treat it as a service issue if the E-stop stays engaged, the same alarm returns, or the controller gives no clear reset path. Also stop if the machine starts unexpectedly, makes an unusual sound, or shows signs of heat or damage.

Record the model, controller, fault text, and what happened just before the stop was pressed. Share those details with the service provider, and leave the compressor isolated as directed by its manual.

If the motor itself won't start after the safety condition is resolved, What to Do If Air Compressor Motor Won’t Start? covers common motor-start symptoms. A compressor that keeps running when it should stop is a different fault; see Why Is My Air Compressor Not Shutting Off?.

Which products help with compressor-related tasks?

These products suit separate air-compressor tasks, not resetting an Atlas Copco emergency stop. Use the compressor's original safety controls and qualified service for an E-stop fault.

The DEWALT D55154 is an electric, wheeled compressor with a 4 gallon tank and a 1.1 hp motor. Its dual universal quick couplers are intended for running multiple tools, so it may suit a different setup where portability matters.

The Dorman 34152 is an A/C compressor bypass pulley for select Chevrolet, GMC, and Oldsmobile models. It concerns a vehicle's air-conditioning compressor and does not fit or repair an Atlas Copco air compressor.

The VIAIR 400P/40043 is a portable 12V tire compressor with a 25 ft hose and a maximum working pressure of 150 PSI. It is for tire inflation, not for diagnosing or restarting an industrial compressor.

What should you do if the E-stop still will not reset?

Keep the compressor stopped and get qualified service if the prescribed release and fault-reset steps do not work. Reset it only after the reason for the emergency stop is understood and it is safe to return the machine to service.

Use the display and manual to distinguish an engaged button from an active controller fault. Don't bypass the safety circuit, force a stuck button, or repeatedly restart a machine with an unresolved alarm.

For a basic reset sequence, review How To Reset Atlas Copco Air Compressor?. If the button itself remains stuck or the fault returns, provide the model and alarm details to a qualified technician.

Frequently asked questions

Why will my Atlas Copco emergency stop button not turn?

The button may still be engaged, or its release method may differ by model. Check the manual for whether it releases by turning, pulling, or another action.

If it releases but the compressor will not start, check the controller for an active fault or safety condition.

Can I reset an Atlas Copco compressor while it is running?

Don't try to reset an emergency stop while the compressor is operating. Keep clear of moving parts, follow the manual's shutdown and isolation steps, and use the emergency stop only for an emergency.

If the machine behaves unexpectedly, leave it stopped and contact qualified service.

Does an emergency stop reset restart the compressor?

Not necessarily. Releasing the emergency stop may only restore the safety circuit; the controller can still require a separate fault reset or start command.

The exact sequence depends on the compressor and controller, so use the instructions for your model.

What if my compressor still will not restart after the emergency stop is released?

Check the controller for an active alarm, then follow the manual's fault-specific instructions. If there is no clear fault or the stop circuit will not reset, don't keep cycling power or open electrical panels.

Have a qualified technician inspect it.