I ordered a new float switch believing that to be the problem, Whilst I was waiting for the new one to arrive I took the old out and checked the normally open/ normally closed functions and they seemed to work perfectly. Not entirely sure what else could cause the pump to run constantly, my next guess would be to replace the pressure sensor as surely this is linked to the drainage system in some sense?
I have also replaced the inlet water valve which is integral to the inlet hose with this model apparently so have ruled that out also.
Would it be possible for a pump to have shorted and run constantly or would it need an input signal from somewhere to do so?
Chris
November 2017