In general the aux battery has nothing to do with running the 3 way
fridge on 12 volts. These fridges only run on 12 volts while the engine
is running. Some people modify the wiring that goes to the fridge to
allow the fridge to run on 12 volts from the aux battery even when the
engine is off. The battery will last several hours but not all night.
That is why it is best not to wire it this way unless you are extremely
careful in operating the fridge. No battery will have a long life if it
is completely drained over and over again. The real purpose of the aux
battery is to run lights, stereo, etc while camped without danger of not
being able to start the engine in the morning. When you stop for the
night the fridge should be switched over to propane since otherwise the
cooling stops when the engine stops. If you wire the aux battery to run
the fridge even when the engine is stopped you will be opening a large
can of biting worms. Care must be taken.

Mark

dusty edwards wrote:

> so, in other words, without the aux. batt., you can't use the 12V
> function of the fridge while driving?
>
> sorry for the back and forth...........trying to educate myself.  i
> didn't realize that this was the case.
>
> On Jul 28, 2005, at 7:32 PM, Loren Busch wrote:
>
>>  RE: Whats the Advantage of the aux battery....
>> Although the aux battery will not handle the fridge for very long it
>> allows the use of 12v on the fridge while traveling, then immediately
>> switch to propane or shore power if available.
>>
>> Many people add addition 12v outlets and wire to the aux battery to
>> run TV sets, stereo, laptops, etc.  In addition to the re wiring of
>> the interior lights, etc. already mentioned.
>>
>> To find out what may have been added to the aux battery take a look at
>> the wiring on the positive terminal.
>>
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