Air Compressor Won’t Start

Air Compressor Won't Start

Troubleshoot the machine with this guide if your air compressor won’t start. Most times, people don’t understand what happens inside pneumatic systems. Instead of jumping to any conclusions, try to understand the likely causes of faults.

It’s hard to pinpoint the exact fault without troubleshooting the equipment. If the cut-in pressure setting is wrong, it will affect the position of your pressure switch. A range of factors can distort the smooth operations of compressors. Let’s share these factors with you.


Air Compressor Won’t Start – Is There Power?

Apart from access to power, every air compressor has its power requirements. While some air compressor models run on fuel, others depend on electricity, starting capacitors, and induction motor. It’s not advisable to run electric air compressors without understanding some technical jargon.

Is the air compressor’s electrical power plug intact? However, the basic principle for electric compression systems is to connect the machine to a wall socket.

Ensure that its power plug is not out of the wall socket. Avoid power bars and power strips because they don’t support the direct connection of machines to electricity sources.

Operators should be careful with extension cords because they come in different gauge ratings. To avoid choking the power that goes to your compressor, use extension cords that have between 10 to 25-gauge wires.

As your local electrical repair shop technician to recommend the best electrical accessories for your air compressor.

Check The Compressor Switch If Air Compressor Won’t Turn On

When my Campbell Hausfeld compressor stopped working, the power switch couldn’t turn on the compressor. It also affected both the automatic run sensor and inner circuit units.

Air compressor troubleshooting is important because it can help operators to detect minor faults. A trip-off condition on circuit breakers of air compressors’ motor can make them not to start. Also, power might not have gotten to the ON/OFF and the pressure switch.

Operators can confirm the flow of electrical current with some simple diagnostics tools. Air compressors work with pressure switches, pumps, motors, and other components. 

Usually, air compressor circuit boxes with a partial connection can cause constant stops and starts.

Capacitor And Relays Fault

Faulty capacitors can wreak a lot of havoc on air compressors. There’s a proper way of troubleshooting this unit, and it’s with a hard start capacitor.

If the technician confirms that your air compressor’s capacitor is broken, a replacement is the best way to resolve this issue.

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Start relays give signs like the capacitor when there’s a fault. Like capacitor replacements, a new start relay can bring your air compressor back to operation.

Air Compressor Stopped Working – Did The Circuit Breaker Trip-Off?

Mechanical equipment that uses electricity often work with circuit breakers. Circuit breakers will trip-off when power surge blows their fuses. Also, circuit breakers offer protection for power panels and equipment.

They could trip-off to protect your air compressor when there’s a very high voltage. If the fuses are bad, you will need fuse replacements before starting your air compressor.

However, it’s better to test the wall socket (for your air compressor) with a trouble lamp. The result will confirm whether electrical power gets to the socket.

The compressor will not start when an in-line fuse inside your air compressor is faulty. Usually, circuit breakers trip-off if the fuse blows during operation. Check the wire connections of the compressor to confirm it’s not a case of an electrical short circuit.

Normally, wires stray outside the proper pathways of electrical circuits. This error can blow your air compressor’s fuse or trip-off the circuit breaker.

Operators might be lucky to have a trip-off without blown fuses. All they need is to confirm basic checks and push the reset button.

The Kobalt air compressor reset button is easy to use too. Electrical problems with air compressors can get worse too.

Sometimes, your Central pneumatic air compressor keeps shutting off if the circuit breakers malfunction.

Air Compressor Won't Turn On

Air Compressor Not Turning On – Is The Pressure Switch Faulty?

Check the pressure witch if the air compressor motor won’t start. Unplug the compressor from the electrical outlet, and bleed air from the tank. To carry out this process, open the drain valve and release the air.

Attaching a blowgun to the drain valve can empty water vapor and air from your compressor tank properly. Don’t forget to wear safety goggles before carrying out this process.  After closing the drain, ask an assistant to plug the compressor and flip the pressure switch lever to the ON position.

Then, try to observe any ‘click’ sound from the pressure switch. Even an ultra-quiet air compressor’s pressure switch will produce this sound.

If the compressor works by indicating movements of points, your electric motor is receiving power and the pressure switch is not faulty.

Usually, the Multimeter device helps to confirm if the current is flowing to both the motor circuit and pressure switch. However, your technician might carry out a pressure switch adjustment on your air compressor.

Porter-Cable Air Compressor Won’t Turn On

After using a portable PORTER-CABLE air compressor for home garage applications, the pressure switch had some faults. It was an efficient small air compressor that ran quietly. Since the compressor tank will not compress air, its low pressure caused a ‘clicking’ sound in the pressure switch.

The clicking sound indicates the pressure switch trying to send electrical power to the compressor motor. A pressure switch replacement got my air compressor operational.

Air Compressor Not Turning On – Is There Enough Oil?

Oil-lubricated air compressors need a constant supply to run efficiently. When the pump’s oil level is below the manufacturer’s specification, your air compressor might be in danger. Check the oil level, and inspect under the pump area for leaks.

When your air compressor’s oil viscosity is off, you’ll need to drain and replace the oil immediately. Refill the oil tank with lubricants that have the right viscosity. If you put a wrong compressor oil in your machine, you could get away with the mistake in the long term.

However, the oil’s additives will damage the compressor pump’s components later. It will give a ‘knocking’ sign when the air compressor tries to start but won’t run.

Our DEWALT Pancake air compressor won’t turn on, and we didn’t know the base was tilted because of an uneven surface. Each time there was an oil refill, oil flowed to the side of the machine on the lower surface area.

Normally, mechanical systems that require oil won’t turn on when oil levels are low. It’s a safe way of shutting down the system and protecting other components. To fix this simple problem, move your air compressor to even platform and addition vibration pads.

Is Your Air Compressor Unloader Valve Stuck?

An air compressor with reciprocating piston uses an unloader valve to blows off air pressure to 0 bar. However, this process occurs after the compressor stops working. If the unloader valve doesn’t unload during a cut-out, your air compressor will not start.

In rotary screw air compressors, the loading valve works like an unloader valve. In the Bostitch 150 PSI air compressor, the unloader valve is close to its pressure switch. You can also actuate this valve with the pressure switch.

When the unloading valve is faulty, it either stays in an open or closed position. A closed unloader valve will give startup problems to your compressor. Also, these faulty unloader valve problems might trigger a blow-down of compressed air. However, there will be a continuous leak of compressed air with a stuck-open unloader valve.

An air compressor for home garage applications uses universal unloader valves. When the air compressor won’t build air pressure due to a faulty unloader valve, install a replacement valve from another brand. 

An unloader valve from California Air Tools can fit into a DEWALT. However, you must ensure that your replacement valve aligns with the connection of your compressor’s pressure switch.

Central Pneumatic Air Compressor Won’t Start – Check The Receiver Pressure

Sluggish build-ups of receiver pressure can affect the operations of air compressors. The accumulation of dirt in air tanks can impede an air compressor’s pressure rebuild process. Usually, manufacturers recommend air compressor owners to clean or change filthy air filters.

Air leaks from loose joints also lead to lagging receiver pressures. However, air filter replacements and tightening of joints will resolve these problems. You will notice a slow receiver pressure buildup when the Husky air compressor won’t turn on. It might be from its insufficient compressor speed. Get a technician to check the compressor’s valve (intake or discharge) plates.


Is your air compressor not working? Our guide provides options for troubleshooting your machine. The Harbor Freight air compressor reset button can help during a tripped circuit breaker problem. These tips might save you from spending money on repairs. However, you should take the air compressor machine to a repair shop when it doesn’t work.

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