Went to a customer's house today that was having problems with their GFI tripping in their basement. All the basement lights, and recepts., plus condensate pump for AHU unit, and the alarm circuit for the sewage pump was fed off the load side of a GFI outlet. At first we didn't know what was tripping it. By troubleshooting it through the boxes, I traced it to the outside sewage pump control box. It controls the circuit board and alarm circuit floats. I disconnected the board and it cleared the circuit up. As far I can read, it is not required for a circuit like this to be GFI protected, in fact the pumps I have worked on in the past have had a separate circuit for the alarm circuit. It's holding now, but it probably will go out again. Not sure what in the control box is causing it. I first thought it might be one of the floats shorting out, but had plumbers check it and that does not seem to be the case. I did find out it was tripping between neutral and ground, and not hot to neutral. After thinking it through again, I'm thinking it may be in the circuit board somewhere, since the floats only break the hot and no neutral is involved. There have been some pretty bad storms here lately, so lightning may have something to do with it. But that all said, I've talked myself into running him a separate 15 amp circuit from the panel on a regular breaker if he calls again. If any other thoughts, I'm open... thanks.. Steve
