Hello Charlie, Apologies....you are quite right. So the test might be to have one person in the galley and the other in the engine room.The galley person switches the watermaker on and sees the red LED. The other person pulls a connector off the probe and at that moment there should be a clunk from the solenoid and the green LED should come on. My bet is that it will do nothing until the two minutes pass and I look forward to a report from someone with a boat in clean water to do the test. I also hope that Joel or Amel will give a full explanation of the installations so that if there is no detector circuit one can decide whether to fit one. Having seen the pics of the damaged washing machine parts on Blue Marine I would not hesitate. My installation has been faultless except last summer when the capacitors on the big electric motor burnt out. The size had been painted over but I got a quick reply from the makers, they are 2 X 30 MFD or 1 60 MFD and 250 volt of course. They are very cheap and easily fitted and should perhaps be in the spares kit for transoceanic voyages. The electrician told me that such failures are relatively common on induction start motors.