Dometic Fridge not working

[Ralph L. Fullenwider]

Hi John:

Ok lets do a little troubleshooting for a minute.
1. Remove all power to the circuit board and remove the 110 vac source,
should just be a plug in
2. locate the 110vac heating element located, attached to the flue tube.
3. Being sure it is the 110vac heating element, attach a cheater cord with
wire nuts to the heating element wires alone and plug it into a hot 110vac
out let. This should start the refer to cool. It will take a few minutes to
feel inside or you can gently touch the flue tube to see if it is getting
hot. If this works then you know the absorption unit is working.
4. Do you have the dometic circuit board or the dinosaur board? either way,
we need to next check to be sure the electronic thermistor is properly
attached to the fins inside of the lower part of the refer. It may be bad,
to check this, remove the thermistor and get a glass full of ice cubes and
a little water in the glass. connect the meter to the leads of the
thermistor and jot down the reading on the meter. Set the end of the
thermistor in the ice water and in about 2 minutes you should see the meter
go to open, no connection or meg ohms. if it does this, then the thermistor
should be ok, if it does not then replace it.
5. check all connection on the eyebrow ribbon cable. Your looking for
corroded connections, and check the ribbon cable to be sure it has not
rubbed through with vibration.
6. check the flue tube to be sure it is not plugged tight with mud dobbers
or what ever.

Be sure to double check that you in fact have 12vdc going to the board. If
you open the refer and the light comes on you can usually be sure there is
12vdc present to the circuit board.

What we are looking for are the common things that will keep a 3 sources of
heat from working.

This is a start, then when all else fails, if you know someone with a pal
or dinosaur board tester, have then check the board with that.

only 5 major things to keep all three sources from working,,, that I
can think of off the top of my head.

1. lack of 12vdc to the board
2. bad thermistor
3. plugged flue tube
4. board
5, Eyebrow inop

Ralph

At 05:54 PM 6/6/2005 +0000, you wrote:
>Hi Ralph,
>
>It does not cool or turn on, either through gas, ac or dc--essentially
>it's a dead unit,
>except for the fact that I do read juice going through the three fuses on
>the panel with all
>the diodes. My usually reliable electrician friend was befuddled. The
>unit model (not the
>original is, RV (or maybe P4) 2807. I'm pretty sure it si not the original.
>Thanks for any advice.
>
>--- In WanderlodgeForum@yahoogroups.com, "Ralph L. Fullenwider"
> wrote:
> > John:
> >
> > Need a little more info.
> > 1. Does it cool on any setting at all,,, 110vac, lp or if a 3 way on 12vdc
> > 2. do the lights on the eyebrow come on? does the light in the fridge come
> > on when door open?
> > 3. need model as well.
> >
> > Safe travels,
> >
> > Ralph and Charolette Fullenwider
> > Dream_35_Team
> > '85FC35 in Oklahoma
> > Ralph's RV Solutions
> > http://home.swbell.net/rlf47/index.htm
> >
> > At 03:00 PM 6/6/2005 +0000, you wrote:
> > >The fridge on our 78 FC 31 stopped working. There is power going through
> > >the fuses--in
> > >fact, it has a new solid state circuit board put in last spring (to the
> > >tune of $300.00, which
> > >I am trying to avoid shelling out again). Can anyone think of some
> > >obvious areas to check
> > >before slinking back to the RV mechanic? Thanks very much.
> > >
> > >On a side note, the Middle school where I teach English, just had an
> > >auction. As a last
> > >minute item I parked my bluebird in the parking lot and offered a
> night of
> > >camping in a
> > > campground. The bidding for Old Blue was crazy; eventually the one
> > >noght trip went for $6500.00--by far the most for any item, including a
> > >trip to Hawaii for
> > >four.
> > >
> > >John Fitz
> > >78 FC 31 3208
> > >Maynard MA
> > >
> > >