Date: Mon, 07 Jul 1997 08:16 -0600 (MDT)
Sender: Vanagon Mailing List <email@example.com>
Subject: Dometic fire alert (at least for the 182B)
First let me admit that my experience may have been a fluke.
You may recall that a week ago I described a situation which rendered
my fridge partially inoperative. I was pre-cooling it on propane,
parked the car in front of the house, came out 10 minutes later and
opened the sliding door, and was greeted by a rush of smokey air (like
someone had smoked a cigarette or two inside with the windows shut).
Anyway, the 8A fuse (behind the driver's seat) was blown and the
circuit was shorted. In reviewing the wiring diagram, I surmised that
the fan motor had shorted out. In order to run the fridge on 12V and
110V, I pulled the one wire from the three-prong plug (though of
course I would be running without the fan, and wouldn't have the
Well, I pulled the fridge this weekend and here's what I found:
The fan had caught fire! The motor was there, but the fan blade
assembly (and all other plastic pieces of the motor) was gone.
The wires were melted off and fused together.
BUT IT GETS WORSE
There's a 2" high portion of the wall paneling that "frames" the
backside of the opening; a 3" wide section of this was burned down to
the floor (probably as a result of the burning, melted plastic of the
fan blades dripping down on it).
Why the whole vehicle did not go up in smoke, I don't know!
THE FIX (I think)
I was never too happy with the fan motor circuit having power all the
time, even when the fridge was not operating (it gets hot enough here
in New Mexico to kick the fan on when the car is sitting in the
parking lot), and since there didn't seem to be an "automatic" way, I
decided to install a switch. And while I'm at it, a secondary fuse
(with a lower rating, to be sure).
I had already purchased one muffin fan (cigarette pack size in Derek
Drew's "fridge manual") to add to the back. I returned to Radio Shack
and bought another one, part # 273-243 (to make it two), plus the
small one 273-240 to install inside, a low profile DPDT rocker switch
275-695 (mounts in a 5/8" hole), a low profile panel mount fuse holder
270-368, some 5A slo-blow fuses (though I think I'm gonna go back and
get some even lower-rated ones - say 3-amp), and nylon wire ties. I
also picked up (elsewhere) a sheet of aluminum, 14 gauge automotive
wire, some clear silicon, and shrink tubing.
Examining the "control" panel atop the fridge, I found that there was
space for the rocker switch right were the Dometic logo was, and that
the fuse holder could be installed between the pump and the
thermocouple hold-down button. I drilled the two appropriately-sized
holes using wood-boring "spade" bits at low speed in an electric drill
(this is THE way to drill plastic; twist drills don't cut perfectly
After determining the proper orientation for the fans, I tie wrapped
them together through their mounting holes, and then tie wrapped them
to the bottom of the lower set of "fins" - BTW, how hot do the fins
get? Are the fins likely to fatigue the wire ties to the point of
breakage? Should I figure out another system to mount them?
I connected the wire pairs from the fans - oddly, the RED wire is the
negative and the BLUE wire is the positive - and after slipping shrink
tubing on the wires, soldered the RED fan wires to the fridge's BLUE
ground wire, and the BLUE fan wires to the fridge's YELLOW wire which
comes from the thermo switch. Slid the shrink tubing over the solder
joints and shrank it.
I opened up the cover over the terminal block and found the yellow
wire that goes to the thermo switch and removed it. I then installed
a new wire from the terminal block to the "in" side of the fuse, a
wire from the "out" side of the fuse to the two center terminals on
the rocker switch, and a wire from one of the "on" terminals of the
rocker switch back to the yellow wire that leads to the thermo switch
(again insulated with shrink wrap). I made sure to run the wires
along with others, wire-tying them as needed and keeping them away
from moving parts. I now have a fused and switched circuit to control
the fans. I also installed the small fan inside the fridge with
silicon, drilled a small hole in the top for the wires to pass
through, grounded the RED wire at one of the grounding terminals, and
extended the BLUE wire to run to the second available "on" terminal on
the rocker switch. Now the switch will also control the inside fan.
I squeezed silicon all around the hole where the wires go to the
inside fan to seal the hole and protect the wires. I also reinstalled
the terminal cover.
Before I reinstall the fridge, I'm gonna line the rear "floor" and
lower back wall of the opening with some of the aluminum sheet.
Hopefully all of this work will make the fridge safer to use (and
leave unattended for 10 minutes!) in the future. I think I'm gonna
install a smoke detector, too!
Please, please pass on any comments you may have about my ideas.