Hi Folks,
Just stopped in for a few questions for my dad-in-law.
He has a late model F-350 Super Duty with the 7.3 deisel. He has dual
batteries and the
When they hooked up the wiring for his new Lance camper, they needed a
direct line from the battery to the fridge so it would run when
parked. He had to talk them into putting a 40 amp breaker inline, they
weren't gonna.
They ran the line from the battery on the drivers side. His questions
are:
Should they have used the battery on the other side instead? Is it
like a dual battery setup on a boat, where one is for starting, the
other is for "house" use?
My thoughts were that the batteries are probably in parallel, and they
would both be drained by the fridge draw when he parks too long. (He
has a Norcold fridge, which I think is propane as well, so maybe it
switches over automatically so this drain doesn't happen?)
Thanks for the help
Donny
Charles Kerekes - 26 Jun 2005 19:57 GMT
Danny,
What year is the F-350? I have a 2000 F-550 with the same diesel engine
and spent a good amount of time tracing the wiring down of the dual
batteries. In my truck they are definitely wired in parallel (to double
amperage). I've heard that sometimes one battery is isolated for
starting only, but that is not the case in my F-550. I assume all of
the F-series diesels have a similar setup due to the large amount of
starting amperage required. If that is the case then both batteries
will be drained by the fridge.
Is it possible to switch out the fridge to one that also runs on
propane? When I bought my 2003 RV, they told me it runs on AC and
propane. I asked why it also does not run on DC and they said those
models typically leave you with dead batteries. Something to consider.
Charlie
Changin' Gears
A web site about the recreational vehicle (RV) lifestyle
http://changingears.com
Tyrone - 26 Jun 2005 20:48 GMT
> Hi Folks,
>
[quoted text clipped - 22 lines]
> Thanks for the help
> Donny
The batteries are wired in parallel. The fridge will kill them both if
the batteries are not kept charged. The proper setup should have a
separate house battery for the Lance. A much lighter wiring connection
will be necessary to connect that battery to the truck charging circuit
through an isolator. The isolator will allow the Lance house battery to
charge from the truck but, will not allow the fridge to discharge the
trucks two starting batteries.
Dave D - 27 Jun 2005 10:52 GMT
> Hi Folks,
>
[quoted text clipped - 22 lines]
> Thanks for the help
> Donny
As others have stated, the correct way to provide 12vdc to the camper is a
third battery charged through an isolator. The isolator allows the
alternator to recharge the third battery but prevents discharging the two
truck batteries required for starting. Three way reefers (ac, dc, gas read
propane) have gone out of popularity in most rvs, the exception being slide
in truck campers. However, even when running in the gas (propane) mode 12vdc
is required to hold the propane inflow valve open while the fridge burner is
lit. The same applies to your furnace in the camper. As you can see, a
separate battery is really "de rigeur" unless you are very careful or have a
very strong arm and heavy duty crank to start your truck. <G>.
Dave D
Donny - 27 Jun 2005 20:12 GMT
>> Hi Folks,
>>
[quoted text clipped - 35 lines]
>
>Dave D
Hi Dave, and all who have replied.
I checked with my dad-in-law, he has a third battery in the camper.
I'll see if it has an isolator. If there's a battery in the camper,
why would the dealer need to run a line from the other batteries?
Shouldn't the camper battery be sufficient to hold the propane inflow
valve open when parked?
Thanks, we're getting there.
Donny
Dave D - 28 Jun 2005 11:52 GMT
> I checked with my dad-in-law, he has a third battery in the camper.
> I'll see if it has an isolator. If there's a battery in the camper,
[quoted text clipped - 5 lines]
>
> Donny
The dealer ran a hot line from the truck batteries to the camper batteries
so that the latter will be recharged when the alternator is turning. The
isolator separates the truck battery from the camper batteries until the
alternator is providing charge voltage, then it allows flow to the camper
batteries to recharge them. When this is not the case it prevents the
camper battery demand from draining the truck batteries. This way you don't
wake up to a no start situation.
Donny - 28 Jun 2005 14:46 GMT
>> I checked with my dad-in-law, he has a third battery in the camper.
>> I'll see if it has an isolator. If there's a battery in the camper,
[quoted text clipped - 13 lines]
>camper battery demand from draining the truck batteries. This way you don't
>wake up to a no start situation.
He was right in requesting an isolator from the dealer, then. Right
now he doesn't have one, so the fridge, when parked, draws from all
three batteries, right? I can see where this would be a problem.
They're on their way home now. I'll call them and make sure they get
one installed as soon as possible.
Thanks to all who replied, and have a good summer.
Donny
www.picturetrail.com/sixbennetts
Dave D - 28 Jun 2005 11:55 GMT
///snipper snipper///
> Hi Dave, and all who have replied.
>
[quoted text clipped - 7 lines]
>
> Donny
Sorry about the previous post, Donny, I had a senior moment and depressed
the send button long before I was ready... Ah, well...I hope that post
cleared up any questions...Good luck...
Dave D
Mellowed - 29 Jun 2005 04:19 GMT
I'm coming very late on this, but, there should be a pair of relays
somewhere around the Master Brake cylinder that will only connect when
the ignition is on. When the ignition is off the relays open isolating
the camper battery from the truck batteries. When the ignition is on,
the alternator charges the camper battery.
: >> Hi Folks,
: >>
[quoted text clipped - 47 lines]
:
: Donny