DGrid39
Virginia
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Does anyone know approximately how long a 27 series deep cycle battery would run a 3 cu ft Fridge?
Does the fridge run off the truck battery while the truck is running or the camper battery that is charged by the truck altenator?
I know, I'm a slow learner...
Thanks
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downtheroad
Pacific Northwest
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The frig will be cooling using propane and only using very little juice from the batt to run the control board. (unless you are plugged into shore power. Then it will use electricity 120v to cool)
The electric draw on the frig will come through your converter and thus through you camper battery which will be charged by the truck's alternator or through shore power if you are plugged in.
Did I confuse you even more..I think I confused myself...
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DGrid39
Virginia
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I forgot to say that I won't be using propane this trip..Only 12v DC & shore power..There will be about 8 hours that I will have to use the camper battery only..
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pianotuna
Regina, SK, Canada
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Hi,
The fridges in general work very poorly on 12 volt. Better plan on some freezer packs or get an inverter. Or use propane.
My fridge draws 12 amps on the DC cooling setting, so 8 hours would be 96 amp-hours--way more than is recommended to draw from a single battery.
Regards, Don
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88lover
Florida
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If it draws 12A a 27 Lifeline would have a 5 hour reserve capacity
Lifeline Battery
Rated Cap.
Amp. Hrs
20 Hr Rate
100
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pianotuna
Regina, SK, Canada
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Hi 88lover,
A group 27 lifeline has a 20 hour rate of 100 amp-hours. No way you want to take it down to 4 amp-hours or 4% state of charge.
Life Line capacities (scroll down)
88lover wrote:If it draws 12A a 27 Lifeline would have a 5 hour reserve capacity
Lifeline Battery
Rated Cap.
Amp. Hrs
20 Hr Rate
100
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DGrid39
Virginia
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pianotuna wrote:Hi,
The fridges in general work very poorly on 12 volt. Better plan on some freezer packs or get an inverter. or use propane
My fridge draws 12 amps on the DC cooling setting, so 8 hours would be 96 amp-hours--way more than is recommended to draw from a single battery.
My wife is really afraid of propane..Will the fridge start up automatically in the gas mode or is there something else I need to fire up other than turning the propane bottle on...
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Atchafalaya_man
Lafayette, Louisiana
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You've given a clue as to a future disappointment you will experience. You can't just 'turn on a propane bottle' and everything will light up just fine.
If you are turning on the propane bottles just before switching the fridge to propane, it will not likely light. Same goes for your furnace and water heater.
You must purge the air in the gas lines by lighting your stovetop burners (by hand usually) for a few moments. Ten seconds of burn is usually enough.
Once they have lit and been extinguished, you have moved the air out of the line, and the gaseous propane through the lines to the fridge and other appliances.
At this point, if you have an "Auto" setting on your fridge control panel, it should switch to propane on its own. If it runs out of propane, it would then automatically switch to 12 volts. If you start a genny, or if you plug into shore power, it will extinguish the propane, and go to 120v operation, all without touching a thing.
Should you have an older unit, you may have to press a button labeled 'gas' or '12v' or "AC".
If your wife is afraid of the propane onboard, you might as well buy a small generator to run your fridge for anything longer than just a few hours on 12v....unless you build up a pretty big 12 volt battery bank for your camper.
She's worried over nothing if your equipment is modern and in good condition. Point out to her that practically EVERY camper you see ANYWHERE uses propane as an everyday energy source at some time in the day.
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buggsy
Harveys Lake, PA
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First of all, how well it will work will depend on how hot it is. Ours will do OK on and 70 degree day, but when it's in the 80's forget using 12v. As far as the battery, depends on how it is wired. In my case, it will use the camper batt, but there is a charging line from the truck to the camper so if the truck is running, it will (theoretically) pull from the camper batt, the truck batt and the alternator. I use 12v on short or cool weather runs, propane on long or hot weather runs. Note there should be a thermocouple on the fridge such that if the fridge goes out on propane, it will automatically shut down the propane supply.
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pianotuna
Regina, SK, Canada
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Hi Dgrid39,
My Fridge uses 3500 watts in 24 hours, on the 110 volt setting. Since a *large* battery only stores about 1200 watts, and since for them to have a long life span we can only use 50% of that energy, to run the fridge on an inverter, six large deep cycle batteries would be needed--and then there needs to be some way to recharge them back to 100% state of charge.
The options are to run a generator, or to get over the propane fear.
DGrid39 wrote:My wife is really afraid of propane..Will the fridge start up automatically in the gas mode or is there something else I need to fire up other than turning the propane bottle on...
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