GFCI Risks? Update

Paul D. wrote:
If you are going to replace the gfci , read the labels carefully. There has been a manufacturing change:
The "line" terminals are now at the top and the "load" terminals at the bottom near the ground (green) . As pointed out by an above respondent the polarity on these is critical for proper operation.

...........

This GFCI receptacle is OEM from the trailer built in Oct 2002.

1. Reading the instruction sheet ( for the first time natch! :( ) I see it says for testing your work after installation, that if you get line and load reversed, "...the GFCI will still operate like an ordinary receptacle, but it will not interrupt a ground fault"

That doesn't agree with this thread on that.

2. It is a Pass and Seymour Legrand made in USA, marked "20a 2 pole unit". On the back it is marked line and load but to me they are not "top" and "bottom". The Line (from breaker) is on the end where the outlet on the other side's ground prong is, which I would have "down". Anyway it is marked.

What I never did was determine which of the two cables coming into that box is "from the breaker" so it is 50-50 whether I had them reversed.

I suppose it would be easy to tell which is from the breaker by seeing it is "live" with the breaker on, while the other cable is dead ?

3. This GFCI receptacle was in the entertainment centre. The bathroom receptacle on that same circuit is not GFCI, but I suppose it is on the load side, because it is dead when the GFCI is popped. Should I put the GFCI in the trailer's bathroom (if the box will fit for depth) ? --ie was it a goof that it was put in the entertainment centre ?

The other GFCI is the "galley" receptacle which is on a different 15a breaker. It didn't pop when this one did, so the fault seems to be just on this one circuit.

--The "20a" marker is strange since the outlets have the standard 15a slots, not the sideways and vertical combo slots you see with a 20a. Whatever, in the trailer it goes in a 15a circuit with a 15a breaker.