I probably need to call an electrician after the weekend to figure out what is causing the problem with my GFCI, but want to make sure I understand correctly how it works before wasting what likely will be a couple hundred on a call for someone just to tell me I'm an idiot.
I recently set up a 75g tank and decide I should convert the outlet for the tank to a GFCI. There are two sets of wires in the box. It works fine with just the live wires connected to the GFCI line terminal; however, when I add the second set of wires to the load terminal, the GFCI trips and won't reset.
It appears that a large portion of the lower level (walkout basement) is on this same circuit. So, I can't convert to GFCI without losing power to most else downstairs. I assume this means there is a problem with the other outlets or baseboard heat that may be connected downstream.
If I connect all 4 wires in the box to the line terminals, until I can get an electrician, am I correct in understanding that the receptacle (tank) will be protected but the problems will remain downstream and they will continue to not be protected?