Piston not sealing or poor sealing;

pump fails to prime

1.  Guide shaft lacks lubrication, causing seizure 

and preventing sealing piston from seating properly;

 2.Poor contact between cable and motor terminals, 

or blown fuse; power supply interrupted, sealing piston inoperative

1.Apply sewing machine oil to guide shaft:

2.Check and reconnect power supply

Leakage in connecting hose;

 pump cannot create vacuum and fails to prime

1. Clamps at both ends of hose connecting control valve 

and pump are loose due to corrosion or prolonged use, causing air leakage

2. Sealing gasket aged, piston seals poorly

1.Inspect, repair or replace clamps to ensure tight, reliable, air-tight connection                   

2.Replace sealing gasket

Pump fails to start in automatic mode

1. A sensor has poor contact

2.  2.Sensor high/low limits or upper/lower ends installed reversely；

3. Motor or fuse damaged；

4.No liquid in tank; sensor not activated;

1.Restore good sensor contact 

2.Install sensor correctly;

3.Repair motor or replace fuse；

4.Check liquid level in tank

Pump fails to stop automatically

1. A sensor is damaged, causing false action；

2. Solid particles in liquid jam the sensor float, forcing false action                                                          

1. Replace damaged sensor：

2.  Flush sensor float to restore free movement

Unable to switch between auto and manual mode        

A button is damaged

Replace damaged button

Pump fails to start in manual mode

1. Manual button damaged

2. Motor or fuse damaged

1. Replace damaged manual button

2. Repair motor or replace fuse

Motor does not run

1.Motor damaged 2.Power supply interrupted

1.Repair or replace motor 2.Check and reconnect power supply

Pump delivers no water

1.Insufficient priming liquid；

2.Air leakage at a flange, valve or pipe section on suction side；

3.Priming or vent plug not tightened, or missing gasket inside plug；

4.No liquid in tank or pool

Check item by item and address accordingly

Flow rate or head (pressure) below specification

1. Voltage too low, rated speed not achieved；

2. Motor rotating in reverse direction；

3. Bottom strainer clogged, insufficient flow passage；

4. Chronic air leakage at a flange, valve or pipe section on suction side, reducing pump vacuum；

5.Insufficient liquid in tank or pool, causing intermittent air ingestion

Check item by item and address accordingly

Leakage at connection between motor and pump

1. Leakage occurs momentarily at startup then disappears during normal operation；

2. Continuous leakage during operation (possible causes: mechanical seal damaged,

 or actual head/pressure differs significantly from pump specifications)

1. Priming liquid overfilled – not a fault；

2. Check if mechanical seal is damaged;

 recalculate whether operating pressure exceeds pump rated parameters. 

If seal is damaged, consider repair or replacement. If pressure parameters differ significantly, 

consider re‑selection or adjust actual operating pressure