dry camping

[bubblerboy64]

I had no idea that there even was an RV of any type that did not have
propane tanks? Guess that shows how out of touch I am. How about
heat in cold conditions? I guess you would certainly be running the
generator then? I guess you pays your money and takes your choice.
Gasoline or propane. Makes not a lot of difference?
John Heckman
central Pa
1973 FC





>
> Great explanation of the amp hour figure, Pete. Your refrigerator
> shouldn't use that much juice though. If you can keep the door
shut
> most of the time, it should run about 30% of the time. The duty
cycle
> goes up a lot if you're fanning the door. Also, the defrost heater
> uses a lot of juice when it cycles. It will normally occur once or
> twice a day and last for about 12 or 15 minutes. Then the
> refrigeration system has to run longer to cool things back off.
You
> can improve things a lot with a domestic refrigerator by keeping
the
> condenser coils clean and keeping the doors shut as much as
possible.
> Also, if there is a switch on its control panel for "humidity
> control" or some such, you might want to keep it in the off or
normal
> or whatever it's labeled position. This is for some electrical
> heating elements that are in the mullions around the door openings
to
> keep them from sweating in high humidity areas. The humidity
probably
> doesn't get that high inside your coach anyway. They use a fair
> amount of electricity 24/7 when turned on. Not a big issue on
shore
> power, but could be significant when dry camping. A lot of the
newer
> refrigerators solve the sweating issue by routing the hot gas
piping
> from the compressor through the mullions before going to the
> condenser; that's why you'll notice the mullions feeling hot to
the
> touch.
>
> I'd like to see what the actual running amp draw is on one of
these.
> I work on appliances for a living; maybe I can remember to put an
> Amprobe on one and see. I have a digital data logger that I can
leave
> in a refrigerator for a couple of days and tell you exactly how
long
> it's running and when it defrosts. Guess I need to find out how
much
> current it's drawing. Never been an issue in a home, but would be
> good to know for when running on batteries.
>
> Travis, the Newell guy in Lubbock, Texas
>
>
> On Dec 2, 2007, at 7:58 PM, Pete Masterson wrote:
>
> > The primary drain (through the inverters) is the power to the
> > refrigerator. It will limit your ability to operate off the grid
with
> > an all-electric coach. (My '95 is all electric.) Newer
refrigerators
> > are perhaps a bit more economical to operate than the 22 cu ft 2-
door
> > Amana that I have in my coach -- but you're likely to experience
the
> > similar power drain.
> >
> > For example, I have 6 model 4D AGM-type house batteries. These
have
> > about 220 amp hours each. So, 6 x 220 = 1320 amp hours. However,
> > that's an overstatement of what's available, as you can't deplete
the
> > battery more than 50% for standard wet cell or by more than 60%
for
> > AGM batteries. So that would mean there's between 660 and 792 amp
> > hours available from the battery to power all the 120 volt systems
> > that are serviced by the inverters. (I have two, 2500 watt
> > inverters.) Also, don't forget that the inverters cause a loss
(10%
> > or more) while changing the 12 vdc to 120 vac. Don't forget that
amps
> > X volts = watts. So, a 1000 watt refrigerator is about 8.3 amps at
> > 120 v per hour. Convert that to 12 vdc, and its about 83 amps.
With
> > the inverter loss, that's about 95 or 100 amps (per hour while the
> > refrigerator is running)... so that suggests about 6 to 8 hours or
> > perhaps 10 hours of operation (since it doesn't run 100% of the
time)
> > just for the refrigerator. Add the microwave (high draw, but short
> > period) plus the various lights and the 12 volt stuff... and then
you
> > can see that the batteries are kind of limiting!
> >
> > Here's where you have to do some math. First figure out the
> > approximate hourly draw in amps of each appliance that runs on 120
> > volts. Don't forget that _some_ of the lights run on 120 volts and
> > are powered by the inverters. Of course, all 12 volt items and
> > appliances also draw from the batteries. So, you also have to
figure
> > out what 12 volt appliances you have operating. Do not ignore the
> > draw from the Microphor toilet compressor nor from the air-system
> > auxiliary compressor, if you have one (I don't) along with various
> > signal lights, etc. etc. -- well, to be honest, there's a _lot_ of
> > load on a 'bird and without a source to recharge, the batteries
can
> > be drawn down to a dangerous level in just a few days, even when
> > everything is "off."
> >
> > So, back to the refrigerator -- the practical situation is to make
> > sure your house batteries are fully charged. If you have an
isolation
> > switch to "turn off" everything, it would help. Anyway, when you
> > think your batteries are fully charged, isolate them (and unplug
> > shore power), then check the voltage. (This is the "resting"
> > voltage.) For AGM batteries, it should be about 12.9 to 13.0 volts
> > (wet cell batteries are different). Then, turn on the isolation
> > switch (apply the normal load) -- wait and hour, remove the load,
and
> > check the voltage. 12.4 volts is 50% depletion and 12.25 volts is
60%
> > depletion -- do not let the volts drop below 12.25 volts!!! ---
this
> > is "resting" voltage measured from the battery terminals.
> > Measurements drawn from other locations (e.g. a fuse panel) are
> > likely to be much lower due to line losses.)
> >
> > My experience has been that "boondocking" isn't especially
practical.
> > I can shut down the generator in the evening, but I usually need
to
> > restart after about 12 hours or so. So, if I shut down at 8:00 PM,
> > I'll usually need to start the generator by about 8:00 AM the next
> > morning to avoid causing any damage to my batteries. This has
caused
> > a fair amount of heart burn when I've stayed in a CA state park
that
> > had a generator operation ban between 8 PM and 10 AM ... those two
> > hours were nail biting time and I had to shut down any/all items
that
> > made demands on the batteries.
> >
> > My plan (the next time I boondock) is to pull the breakers on the
> > inverters perhaps at 10 PM or so, and see how the batteries are
the
> > next morning. The refrigerator won't warm up much during the
night,
> > if it is not opened and if we're in a reasonably cool location.
> >
> > I've compared notes with another all-electric Blue Bird owner
(just
> > this past weekend at the Lone Star Birds rally in Kerrville, TX)
and
> > I'm of the impression that my voltage drain seems to be on the
high
> > side (so I may need to further explore possible reasons).
> >
> > The reality is that you can probably turn off the generator in the
> > evening then turn it back on in the morning without major
problems.
> > You can run the generator for 3 hours or so to bring the batteries
> > back up to full or near full charge. Then you can shut down the
> > generator for a few hours, then run it for 3 or 4 hours until the
> > time you wish complete quiet at night (or until any required shut
> > down time occurs).
> >
> > The coach can be off the grid without the generator for periods of
> > several hours -- but it will need to have power to recover the
> > batteries rather more often and/or for longer periods than coaches
> > that have LP gas appliances.
> >
> > See Poop Sheets by Phred at:
> > <http://www.phrannie.org/phredex.html>
> > #5 has a thorough discussion of "electrical stuff."
> >
> > Pete Masterson
> > '95 Blue Bird Wanderlodge WBDA 42
> > aeonix1@...
> > On the road at Lubbock Texas following a great weekend with the
Lone
> > Star Birds at Kerrville, TX.
> >
> > On Dec 1, 2007, at 2:08 PM, medpro28 wrote:
> >
> > > Just purchased a 2005 LXi and need some advice on dry camping.
I
> > cook
> > > in bbq contests and sometimes no power or 110 only. Dealer says
I
> > > will
> > > have to use the generator all the time. Although the unit is all
> > > electric, will not use the stove top or microwave while camping.
> > > It is
> > > hard to believe I can't dry camp any length of time and then use
> > > generator to keep batteries up.
> > > Is the dealers advice right or does anyone have thoughts or
> > > suggestions?
> > >
> > > Jerry Smith
> > > 2005 450 LXI
> >
> >
> >
>
>
>
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