Electrical code violation - dangerous

[rbr]

While snowbirding on a Mexican beach, our GFI outlet circuit from the reefer onward went TU while the wife was using a hairdryer in the washroom. Upon arrival home I dismantled multiple wirecon outlet connectors finding:
1) The circuit did not follow the wiring diagram for the trailer thus requiring several extra boxes be removed and inspected, and
2) AIRSTREAM HAD USED 15A BOXES IN A 20A CIRCUIT, forcing 3 12ga
wires into a space meant for 14ga. Over time the back of the box in the roadside bedroom wall had popped loose under the excess pressure
Inside the box the plastic was both deformed by melting and discolored
black by arcing!

I consider myself very fortunate that this circuit lost continuity rather than overheating to the point of a fire! (A friend's A/S Classic moho did burn, due to a short, on Valentines Day). In my 28' Safari I found two of these undersized connectors joining three 20A wires,both upstream of the reefer. In both cases the wires are now securely joined with solder, wirenuts, and long lengths of electrical tape, with 15A pigtails into the receptacles. Had my trailer burned, an astute insurance inspector might have considered this violation to be sufficient cause for denial of coverage.

I further posit that the very small conductive surface area in these connectors, probably less than 2 square millimeters, is insufficient to carry the current flows demanded downstream, and may explain why so many reefers operate less well on shore power, ie. they don't get enough juice.

Really, Airstream, properly sized boxes can't cost extra.

[HowieE]

Yes shallow wall boxes are used in almost every trailer made. It is hard to fit a 4 in. deep wall box in a wall that is only 2 1/2 in. thick.

Not knowing what connection you are describing it is hard to comment as to why melting and discoloration has occurred. Had wire nuts and screw type receptacles been used originally there should not have been a problem of that type.

I would caution putting 14 gauge wire, 15 amp pigtails, on a 20 amp circuit. That is a violation of code. You fuse to the SMALLEST conductor.

As for a 1500 watt hair drier used on anything other than a dedicated circuit you have to accept the likelihood of problems.