tunze auto top up problem ?

[jaggy]

hi when i set up my tunze auto top up and switch it on , pump runs for a few secons and turn off , led goes to green ie level , then for no reason the pump will come on and pumps the container dry , and level alarm goes of ? i have the float up the way and if i pull the float up it does cut pump off , and the water sensor is just under water at the tip , but it will pump and pump ?
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[rvitko]

Is it brand new or a used one? If it is brand new try soaking the sensor in hot soapy water and then wash it very well. This will break the surface tension of the new plastic.

 

[jaggy]

no m8 it is a used one?

 

[rvitko]

Is the sensor clean? You might try soaking it in vinegar. Otherwise I suspect the sensor is faulty and needs to be replaced.