Skip to main content ↑ ↓
Topic: A warning and a question (Read 548 times) previous topic - next topic

A warning and a question

Long story made short - one of the outlets behind our (original) refrigerator caught fire today.  We were home, heard the smoke detector and investigated.  The outlet burned, sooted up the area above it, and put some smoke in the cabin.  Not bad, it has aired out nicely with no deposits of soot or smell inside.

The warning is to look at that outlet in your coach.  We have ARP protection on the refrigerator mechanism, but I never worried about the outlets.

The questions... 

There are two outlets, and the upper one just has a melted cover and the wires are still OK.  Is the upper one for the inverter to supply the fridge AC?

The lower outlet is a melted mess.  There were three Romex lines going to it.  Does someone know what the wires do?  One in and two out?  Two inputs - one for each socket in the outlet, and one out?
Matt B
1998 u-320

Re: A warning and a question

Reply #1 –
Matt,

Once you have "dissected" the outlet, please let us know the origin of the overheating.

Any sign of moisture? Other evidence of causes?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: A warning and a question

Reply #2 –
Have worked on my frig recently,a blowing hard rain will get past the outside cover.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: A warning and a question

Reply #3 –
Quote from: wolfe10 –
Matt,

Once you have "dissected" the outlet, please let us know the origin of the overheating.

Any sign of moisture? Other evidence of causes?
No moisture from fridge or from outside sources.  The outlet is a black glob, with a lot of the plastic gone,  The two plugs that were plugged into it are badly melted as well.

No breakers tripped.

My GUESS is a poor connection between the plugs and the outlet, or a poor connection within the outlet.  I am still surprised that there were three wire sets (nine wires) connected to the outlet.  Not even a boxed residential - one of the "all-in-one" RV type surface-mounted to the plywood.
Matt B
1998 u-320

Re: A warning and a question

Reply #4 –
Quote from: John44 –
Have worked on my frig recently,a blowing hard rain will get past the outside cover.
We had .001 inch on September 20th!  It has been dry for a while.

I have seen rain get by the cover.
Matt B
1998 u-320

Re: A warning and a question

Reply #5 –
I opened the wall under the fridge and I see where the wires go up through the cabinet.  I clipped some electrical tape and there is enough slack in the wires to (I think) replace the outlet.

But if there were one wire in and two out on the outlet, I think I will add a junction box below the fridge, and run a single wire to the outlet.

The outlet above the burned one is distorted from the heat, but did not itself burn.  It will be replaced.

With the power on, one of the three wires has 120V and two do not.  Does anyone know of these wires feed FROM the outlet?  I want to make sure before I start rewiring.
Matt B
1998 u-320

Re: A warning and a question

Reply #6 –
Figure the outlet with a single wire is powered by the main breaker panel and will be dead if running in inverter. This outlet is power for fridge electric heating element.

Figure the outlet with 3 wires has one wire powered from inverter panel and gets it power from a GFCI outlet. The other two wires feed other outlets that are also on the same GFCI (like TV outlet and other outlets around the coach. This outlet is for fridge ice maker. Even if not on GFCI, Foretravel wires many outlets on same breaker by daisy chain cables.

If Fridge was on Electric instead of propane, a lot of current was drawing that plug. And if a heater was plugged into one of the 'downstream' outlets all that current was flowing through that outlet.

And those RV outlets with simple connections that cut the wire through the insulation are potential problems, especially if multiple wires are squeezed together. Replace them all with conventional home outlets and boxes.

We NEVER plug high current appliances, like heaters into any outlet that can be powered from inverter. One reason is if shore power is cut off, and inverter switch is on, batteries can be depleted. Also, on some coaches all current flows through inverter relay when on shore power or inverting possibly stressing expensive charger/inverter.

Re: A warning and a question

Reply #7 –
The stuff Barry and Cindy says is true.  I was wrong about the upper outlet - it also had three wires.

THAT outlet was good enough condition that I could dismantle it and see how it worked.  Shove a continuous wire in a channel, add a cut wire on the top, and snap the back cover on.  The remains of the lower outlet looked similar, so I think they were the same design.  Both had a continuing wire and was the origination for a third.

I installed an electrical junction box under the fridge and pulled all of the existing wires down,  I added wires from the junction box back up to new outlets in residential boxes.  The wires are all together and working.  I still have a mess to clean up tomorrow.

I was confused about why there is two outlets to begin with.  I guess we can decide if the fridge ice maker is on shore or inverter, AND if the fridge itself is on shore or inverter.  I think the bottom outlet is shore only, and the top one will work from shore or inverter.

No power loads in the coach except for battery chargers, an idle inverter, and the fridge with ice maker. 

My guess is that the outlet just got old and corroded and the internal connections were the source of heat.

Thanks all!
Matt B
1998 u-320

Re: A warning and a question

Reply #8 –
Quote from: oldmattb –
I was confused about why there is two outlets to begin with.  I guess we can decide if the fridge ice maker is on shore or inverter, AND if the fridge itself is on shore or inverter.  I think the bottom outlet is shore only, and the top one will work from shore or inverter.


IIRC, Foretravel puts both inverted and shore-only outlets behind the fridge as a "pre-wire" so that those with a separate icemaker option would plug it in the inverted circuit (check your schematics - that outlet is likely on the circuit that says "icemaker" that's in the inverter breaker box.)
Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

2000 U320 36' non-slide / WildEBeest Rescue
2003 U320

Re: A warning and a question

Reply #9 –
The OE. Fridge receptacles come loose and heat up. Remove and replace with a new house type of receptacle.
 

Re: A warning and a question

Reply #10 –
Normally the black receptacle is shore power only and is where the refrigerator plugs into and the white receptacle is where the plug for the ice maker in the refrigerator plugs in, it is supplied power from and through the inverter.
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins