- Electrical installation work must only be executed by qualified personnel.
- Prior to any action requiring touching the machine, let the machine cool down first.
| Problem | Possible Cause | Remedy |
| The machine does not start | At least two power supply leads are interrupted | - Check the fuses, terminals and power supply cables |
| The motor is not supplied with the correct voltage. | - Check the power supply. | |
| The motor is defective. | - Repair the machine (contact us). | |
| The machine does not start; humming noise. | One power supply lead is interrupted | - Check the fuses, terminals and power supply cables |
| Impeller defective | - Replace impeller | |
| Impeller is jammed | - Open the cover, remove foreign body and clean. | |
| - Check the impeller gap. | ||
| Bearing on motor side machine side is defective | - Replace defective bearing. | |
| Motor protective switch trips when starting the machine. Power consumption is too high. | Winding short-circuit | - Check the winding. |
| Motor overloaded. Throttling does not match specification on rating plate | - Reduce throttling. | |
| -Clean filters, mufflers and connecting pipes. | ||
| Compressor is jammed. | - See the machine does not start; humming noises. | |
| The machine runs very noisily. | The machine runs in the wrong direction | - Check the direction of rotation. |
| Bearings lacking grease | - Re-lubricate or replace if necessary. | |
| Defective bearings. | - Repair the machine (contact us). | |
| The machine runs with abnormal flow noises. | The flow speed is too high | - Use larger sized pipes. |
| The silencers are soiled. | - Check silencer inserts, clean or replace if necessary. | |
| The machine does not reach the usual pressure on the suction connection. | Suction or discharge lines too long or section diameter too small. | - Use larger diameter or shorter lines. - Seek advice from your local sales representative. |
| The machine runs in the wrong direction. | - Check the direction of rotation, see Wiring Diagram Three-Phase Motor. | |
| Different density of conveyed medium | - Take conversion of pressure value into account. Contact us if necessary. | |
| Change in blade profile due soiling. | - Check the impeller, clean or replace if necessary. | |
| In case an inlet screen is installed : The inlet screen is partially clogged. | - Clean the inlet screen. | |
| In case a vacuum relief value is installed: The vacuum relief valve is misadjusted or defective. | - Replace the vacuum relief valve. | |
| In case an inlet filter valve is installed: The inlet filter cartridge is partially clogged. | - Replace the inlet filter cartridge. | |
| Leak in the system. | - Repair leak. | |
| Internal parts are worn or damaged. | - Repair the machine (contact us) | |
| Insufficient cooling. | - Remove dust and dirt from the machine. | |
| Ambient temperature is too high. | - Observe the permitted ambient temperature. | |
| Seals on silencer defective. | - Check silencer seals and replace if necessary | |
| Seals in the motor area are defective. | - Check motor seals and replace if necessary |
