What if air compressor does not start again when the air tank is empty?

1, Air Pressure Too High (Tank Not Draining Properly)

Cause: If the pressure switch setting is too high or the tank doesn't release pressure properly, the compressor might not restart.

Solution: Manually release some air to check if the compressor restarts at lower pressure.

2, Pressure Switch Malfunction

Cause: The pressure switch controls the compressor’s start and stop based on pressure levels. If it's faulty or incorrectly set, it may not trigger the restart.

Solution: Check if the pressure switch is adjustable and set correctly. If it's defective, replace it.

3, Overheating or Thermal Overload Protection

Cause: The motor may have overheated, triggering the thermal overload switch.

Solution: Let the compressor cool down, then press the reset button (if available). And do not let me reach max air pressure. The blow molding machine do not need that high pressure.

If your high-pressure air compressor runs and stops when it reaches maximum pressure but fails to restart automatically after using the air, here are the most likely causes and solutions:

1. Pressure Switch Malfunction

• Cause: The pressure switch controls the compressor’s start and stop based on pressure levels. If it's faulty or incorrectly set, it may not trigger the restart.

• Solution: Check if the pressure switch is adjustable and set correctly. If it's defective, replace it.

2. Faulty or Clogged Unloader Valve

• Cause: The unloader valve releases trapped air from the pump head when the motor shuts off. If it fails, excess pressure may prevent the motor from restarting.

• Solution: Inspect the unloader valve, clean or replace it.

3. Air Pressure Too High (Tank Not Draining Properly)

• Cause: If the pressure switch setting is too high or the tank doesn't release pressure properly, the compressor might not restart.

• Solution: Manually release some air to check if the compressor restarts at lower pressure.

4. Overheating or Thermal Overload Protection

• Cause: The motor may have overheated, triggering the thermal overload switch.

• Solution: Let the compressor cool down, then press the reset button (if available).

5. Electrical Issues (Faulty Wiring, Breaker, or Capacitor)

• Cause: Loose wiring, a blown fuse, or a weak capacitor can prevent restarting.

• Solution: Inspect and tighten all electrical connections, check fuses/breakers, and test or replace the capacitor.

6. Check Valve Failure

• Cause: The check valve keeps air from flowing back into the pump. If it fails, pressure buildup may stop the motor from starting.

• Solution: Remove and inspect the check valve; replace if defective.

Troubleshooting Steps:

1. Manually release some air – See if the compressor starts again.

2. Check the pressure switch – Adjust and replace it.

3. Inspect the unloader valve – Ensure it releases excess pressure.

4. Let the motor cool down – Press the reset button.

5. Test the power supply and wiring – Fix any electrical issues.

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