| Fault | Cause | Remedy |
| Motor does not start or motor noise | At least two power supply leads interrupted | Eliminate interruption by fuses, terminals or power supply cables. |
| Motor does not start or humming noise | One power supply leads interrupted | Eliminate interruption by fuses, terminals or power supply cables. |
| One or more phase of winding open | Repair / Replace motor winding | |
| For a single phase motor – capacitor open | Change capacitor | |
| Impeller is jammed | Open blower front cover, remove foreign body and clean | |
| Check or correct impeller gap setting if necessary. | ||
| Impeller is defective | Replace impeller | |
| Rolling bearing on drive motor side / blower side defective | Replace motor bearing / blower side bearing | |
| Protective motor switch trips when motor is switched on. Power consumption too high | Winding short circuit | Have winding checked |
| Motor overloaded Throttling does not match specification on rating Label | Reduce throttling | |
| Clean filters, mufflers and connection pipes if necessary | ||
| Power source unbalanced | Check & rectify power source | |
| Blower is jammed | See fault “Motor does not start humming noise. “With cause: “impeller is jammed.” | |
| Blower unit does not generate any or generate insufficient pressure difference | Leak in system | Seal leak in the system |
| Wrong direction of rotation | Reverse direction of rotation by interchange two connects leads. | |
| Incorrect frequency (on Blower units with frequency converter) | Use Correct frequency | |
| Different density of pumped gas | Take conversion of pressure values into account. Inquire with us. | |
| Shaft seal defective | Replace shaft seal. | |
| Change in blade profile due to soiling | Clean impeller, check for wear and replace if necessary | |
| Abnormal flow Noise | Flow speed too high | Clean pipes. Use pipe with larger cross-section if necessary |
| Muffler soiled | Clean muffler inserts, check condition and replace if necessary | |
| Abnormal running noise | Ball bearing lacking grease or defective | Regrease or replace ball bearing |
| Blower leaky | Seals on muffler defective | Check muffler seals and replace if necessary |
| Seals in motor area defective | Check motor seals and replace if necessary |
