en
Faults, causes and remedies
26
WILO SE 2019-11
2. Thermal motor monitoring has been tripped
⇒ Allow the pump to cool down. The pump will start automatically.
⇒ Pump switches on/off too frequently. Check the switching cycle of the
float switch.
⇒ Excessive fluid temperature. Check the temperature. If necessary, use a dif-
ferent pump.
3. Strainer/impeller blocked with sand/clogged
⇒ Shut down the pump, remove it and clean it.
4. Float switch not operational
⇒ The float switch must be able to move freely.
Pump starts up, but does not supply fluid
1. Pressure pipe/discharge pipe clogged
⇒ Flush out the pressure pipe.
⇒ Flush out the pressure hose.
⇒ Remove any kinks in the pressure hose.
2. Non-return valve contaminated
⇒ Shut down the pump, remove it and clean the pressure connection.
⇒ Replace faulty non-return valve.
3. Water level too low
⇒ Check inlet.
⇒ Pump pumping excessively. Check the switching cycle of the float switch.
4. Strainer blocked with sand/clogged
⇒ Shut down the pump, remove it and clean it.
5. Air in the pump/pressure pipe
⇒ Position the pump at a slight angle to allow air to escape.
⇒ Install a bleed unit in the pressure pipe.
Delivery rate drops while the pump is running
1. Pressure pipe/discharge pipe clogged
⇒ Flush out the pressure pipe.
⇒ Flush out the pressure hose.
⇒ Remove any kinks in the pressure hose.
2. Strainer blocked with sand/clogged
⇒ Shut down the pump, remove it and clean it.
3. Air in the pump/pressure pipe
⇒ Position the pump at a slight angle to allow air to escape.
⇒ Install a bleed unit in the pressure pipe.
