Repair of a Water Pump
| Failure | Cause | Repair |
|---|---|---|
| Water supply is absent, but the electric motor is working | The impeller is blocked or the shaft is rusted | Remove the pump, remove foreign objects from the impeller. During long periods of inactivity, oxidation can cause the shaft to lock up, so check the shaft by hand before removing the protective cover or impeller. |
| - - - | The electrical network parameters do not match the passport data | Check the voltage parameters at the input and the correctness of the connection to the terminal block. |
| The pump is not working and does not produce any sounds | There is no voltage or the electrical circuit is broken | Check the voltage parameters at the input, the integrity of the electrical networks, and the correctness of the pump connection diagram. |
| - - - | The fuse has blown (the electric motor was overloaded) | Replace the fuse. If this does not work, the overload may have damaged the motor windings. |
| The pump operation is accompanied by an unusual noise | There is air in the flow path (possible motor overload) | Release accumulated air. Install an automatic air vent at the top point of the installation. |
| - - - | Cavitation in the pump (accompanied by vibration) | The pressure in the suction pipe should exceed the pump cavitation reserve by at least 0.5 m |
| - - - | Dry run | There is no water in the suction pipe |
| - - - | Liquid level below suction level | Raise the water level or lower the pump. The maximum lift of the pump from the lower reservoir due to the pressure drop in the impeller usually does not exceed 5 m. |
| Pump vibrates | Damaged bearing | Replace and lubricate bearings. |
| - - - | Pump housing not secured | Secure the pump on the frame or foundation according to the project and installation instructions. |
| Water flow or pressure below specifications | Impeller rotates in the opposite direction | Typical for incorrectly connected pumps with three-phase power supply. |
| External motor protection activates during startup | Problems in the electrical part | 1. Check for all phases in the terminal box. 2. Check the fuse contacts. 3. Check phase resistance to ground. |
| Motor protection activates too often | High temperature in the room | The temperature in the room should not exceed 40°C. |
| - - - | Damaged bearings | Replace and lubricate. |
Attention! Water pump repair must be performed after disconnecting the power and draining the area.
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