12 volt Refrigerators

Recpro
made by Ever Chill.
.75A (12VDC) @ 70 degrees ambient reported by user.

BurbMan wrote:

JRscooby wrote:
Change batteries every day? You use that much power?
If you are away from the camper, what is drawing power?

The discussion is around a 12v compressor fridge that would draw a lot more power than an absorption fridge does while running on propane. Somebody posted a model with a power draw of 1.1a @120v, and at that rate, you would get about a day out of a battery. When you come back to camp with the charged battery in the truck, the dead one in the camper would suck it dry.

Ok, they battery is down in about a day. (not been my experience) You come back after say 4 hours of sight seeing. The battery on trailer has about 75% of useable capacity left, right? And the 1 on TV is fully charged. Now if you hook them together, sure the voltage would equalize, But why do that? unhook the one on the camper, and hook cables to the fully charged 1. Next day, or the day after, when ready to go sight-seeing, unplug the TV, hook 75% back up. After 6 more hours, 50%.

JRscooby wrote:
Change batteries every day? You use that much power?
If you are away from the camper, what is drawing power?

The discussion is around a 12v compressor fridge that would draw a lot more power than an absorption fridge does while running on propane. Somebody posted a model with a power draw of 1.1a @120v, and at that rate, you would get about a day out of a battery. When you come back to camp with the charged battery in the truck, the dead one in the camper would suck it dry.

Gdetrailer wrote:

JRscooby wrote:

NRALIFR wrote:

I don’t have solar panels right now, although I could add some now that I have a DC-DC charger that has a solar input. I may add some someday, but for now taking advantage of the charging potential available while driving was a better fit for our traveling and camping style. Up to 40 amps whenever the engine is running. Our trips usually involve a lot of driving, sometimes at night when solar doesn’t seem to work very well, so I needed something I could depend on more.

I have had a off the wall idea for somebody that sets up the camper then spends part of most days out and about in the TV. How mush power does the camper use while you're out? I would think a small battery could handle that for a week or so. Now mount another battery, big enough to handle normal loads for a couple of days on the TV. Driving would keep that battery charged, just hook to camper when get back. Might need to switch batteries if don't move often enough to keep trailer charged...

I am sure there are folks doing this, however, I suspect most folks would get pretty tired of shuffling around 80lb-160lb batteries on a daily basis.

Not to mention even if you had a direct line on the TV to the depleted batteries you would find that the depleted batteries would not get enough charge to warrant this kind of hassle.

Instead, you would have to use some sort of DC-DC charging system or 120V inverter to 12V converter/charger that boosts the TV's voltage up to a higher voltage in order to ever affect any appreciable charge on the depleted batteries.

Then you would have to be running your vehicle for hours and hours non stop. Most times you rarely will need to run a vehicle more than half hr one way and half hr back unless you are planning to take 6hr each way "day trips". Not going to be much charging happening with short trips.

Cost in building up such a system and cost in work plus cost of daily hassle = not worth it to me. That's a younger man's game, over the years I have wised up and look for LESS WORK.

Far better to size the battery bank for the loads and run time expected/needed between charging and perhaps add in some solar to round out and extend your time a bit.

No free meals, no free energy, you have to pay for it somewhere..

If your gonna camp with no commercial power, manup, buy enough batteries and solar to do the job or run a generator.. Anything else is a lot of hassle added to your camping, I don't know about you, but myself, my priority is not attending to more hassle and work and I am not afraid of pulling the gen starter cord if needed if it means less hassle..

Change batteries every day? You use that much power?
If you are away from the camper, what is drawing power? I leave the fridge on, but everything else is off. Now how many hours will a group 27 run that fridge safely? Bet it would be at least a full day on normal hold the cool, with nobody to open the door. (I'm just trumping numbers, but the arithmetic could be done) It would only have drain when the TV is gone. Say 2-6 hours a day, so at least 4 days, and then change CG, or switch batteries. (But if average 3 hr/day good for week)
Now NRALIFR is reporting up to 40 Amps of charge while TV engine is running. A larger battery, mounted on TV, could be recharged fairly fast. Get back to camper, unplug little battery, plug in big 1. Use what power you need for the night, then just unplug from TV, plug in the small, and another day of fun.

Gdetrailer wrote:

Reisender wrote:

ajriding wrote:
The "new" electric fridges, I assume you refer to the Danfoss compressor-style ones? They are wonderful. You posted un-necessarily as there are quite a few post on here talking about them. Try a search next time to see if there are not already 300 post on this exact same subject.

They run on 12 or 24 volts, or when plugged into household current will run on 24 volts converted from the 120v alternating current.

Never use a household refrigerator unless u plan to park permanently.

Why not.

Some folks just believe (mistakenly so) that residential 120V compressors are "energy hogs" and they are fragile and will not survive being jostled on the road..

They are dead wrong on both aspects.

There are some residential fridges that may be less efficient due to the design/layout or use of higher wattage defrost heater and electric door heaters but it is easy to find those just be looking at the name plate max current draw.. Often those will have a 6.5A at 120V rating, but if you search carefully you can find plenty of very low current draw fridges..

Often 10 cu ft "apartment size" are good choice because they typically have the lowest draw and best insulation.. The one I have has a name plate draw of 1.1A for the compressor and 1.6A defrost draw.

I measured mine at 90W for the compressor and the defrost only runs 10 minutes for every TEN hrs of COMPRESSOR RUN TIME.

Compressor runs about 22 minutes per hr..

"Danfoss" compressors typically use 2.5A-3.5A (30W-40W) at 12V so sure they are a little bit more "energy efficient than a direct 120V compressor but in the bigger pix, not all that much. Danfoss compressors also come with a HEFTY price tag and they drag along considerably more expensive, complex and fragile variable speed driver board which adds something else to break down..

Interesting enough, Dometic has brought out a 10 cu ft Danfoss fridge that seems to have a much higher current draw rating than what it should at 15A (180W) at 12V!!! Found that HERE which pretty much makes the argument for Danfoss being more energy efficient null and void..

But hey, some folks just can't part from anything the is marketed for the "RV" market..

The price of that Dometic leaves me cold at $1250! Found that HERE

You can buy a lot of solar and batteries for that crazy price.. Heck my 10cu ft residential fridge cost $300, I can buy 300W of solar plus en extra pair of GC2s and still have money in my pocket..

But, hey, at least it is built buy a "quality" RV manufacturer, right? :R

Every apartment size fridge I looked at had side, back and top requirements that can't be had when in an RV fridge compartment.

Thats why the 12V RV/Off grid types are better.

Gdetrailer wrote:

JRscooby wrote:

NRALIFR wrote:

I don’t have solar panels right now, although I could add some now that I have a DC-DC charger that has a solar input. I may add some someday, but for now taking advantage of the charging potential available while driving was a better fit for our traveling and camping style. Up to 40 amps whenever the engine is running. Our trips usually involve a lot of driving, sometimes at night when solar doesn’t seem to work very well, so I needed something I could depend on more.

I have had a off the wall idea for somebody that sets up the camper then spends part of most days out and about in the TV. How mush power does the camper use while you're out? I would think a small battery could handle that for a week or so. Now mount another battery, big enough to handle normal loads for a couple of days on the TV. Driving would keep that battery charged, just hook to camper when get back. Might need to switch batteries if don't move often enough to keep trailer charged...

I am sure there are folks doing this, however, I suspect most folks would get pretty tired of shuffling around 80lb-160lb batteries on a daily basis.

Not to mention even if you had a direct line on the TV to the depleted batteries you would find that the depleted batteries would not get enough charge to warrant this kind of hassle.

Instead, you would have to use some sort of DC-DC charging system or 120V inverter to 12V converter/charger that boosts the TV's voltage up to a higher voltage in order to ever affect any appreciable charge on the depleted batteries.

Then you would have to be running your vehicle for hours and hours non stop. Most times you rarely will need to run a vehicle more than half hr one way and half hr back unless you are planning to take 6hr each way "day trips". Not going to be much charging happening with short trips.

Cost in building up such a system and cost in work plus cost of daily hassle = not worth it to me. That's a younger man's game, over the years I have wised up and look for LESS WORK.

Far better to size the battery bank for the loads and run time expected/needed between charging and perhaps add in some solar to round out and extend your time a bit.

No free meals, no free energy, you have to pay for it somewhere..

If your gonna camp with no commercial power, manup, buy enough batteries and solar to do the job or run a generator.. Anything else is a lot of hassle added to your camping, I don't know about you, but myself, my priority is not attending to more hassle and work and I am not afraid of pulling the gen starter cord if needed if it means less hassle..

As said, it could be done. Torklift makes a dandy looking little aux battery system that hangs off the truck frame. Of course you have to get the battery up there, and that’s the problem for me as well. Shoulder injuries and surgery make that an impossible task. It’s hard enough getting the single group 31 AGM that weighs 75 lbs into the battery compartment that can only hold that one battery. I have to get on a ladder so I don’t have to pull it up above my waistline. Fortunately, once it’s there, it pretty much stays there. I don’t really want batteries in the truck bed either, as clearances are pretty tight there already.

If I couldn’t count on the amount of road time we typically have on our trips, solar would definitely look better to me. Right now, there would be very little return for the time and money spent. That may change once we no longer have some business to mix with our pleasure, but I’m not totally counting on it. We do like to travel around a lot, and as far as I’m concerned we have a very workable system. The availability of the DC-DC charger will always be higher than solar.

:):)

JRscooby wrote:

NRALIFR wrote:

I don’t have solar panels right now, although I could add some now that I have a DC-DC charger that has a solar input. I may add some someday, but for now taking advantage of the charging potential available while driving was a better fit for our traveling and camping style. Up to 40 amps whenever the engine is running. Our trips usually involve a lot of driving, sometimes at night when solar doesn’t seem to work very well, so I needed something I could depend on more.

I have had a off the wall idea for somebody that sets up the camper then spends part of most days out and about in the TV. How mush power does the camper use while you're out? I would think a small battery could handle that for a week or so. Now mount another battery, big enough to handle normal loads for a couple of days on the TV. Driving would keep that battery charged, just hook to camper when get back. Might need to switch batteries if don't move often enough to keep trailer charged...

I am sure there are folks doing this, however, I suspect most folks would get pretty tired of shuffling around 80lb-160lb batteries on a daily basis.

Not to mention even if you had a direct line on the TV to the depleted batteries you would find that the depleted batteries would not get enough charge to warrant this kind of hassle.

Instead, you would have to use some sort of DC-DC charging system or 120V inverter to 12V converter/charger that boosts the TV's voltage up to a higher voltage in order to ever affect any appreciable charge on the depleted batteries.

Then you would have to be running your vehicle for hours and hours non stop. Most times you rarely will need to run a vehicle more than half hr one way and half hr back unless you are planning to take 6hr each way "day trips". Not going to be much charging happening with short trips.

Cost in building up such a system and cost in work plus cost of daily hassle = not worth it to me. That's a younger man's game, over the years I have wised up and look for LESS WORK.

Far better to size the battery bank for the loads and run time expected/needed between charging and perhaps add in some solar to round out and extend your time a bit.

No free meals, no free energy, you have to pay for it somewhere..

If your gonna camp with no commercial power, manup, buy enough batteries and solar to do the job or run a generator.. Anything else is a lot of hassle added to your camping, I don't know about you, but myself, my priority is not attending to more hassle and work and I am not afraid of pulling the gen starter cord if needed if it means less hassle..

NRALIFR wrote:

I don’t have solar panels right now, although I could add some now that I have a DC-DC charger that has a solar input. I may add some someday, but for now taking advantage of the charging potential available while driving was a better fit for our traveling and camping style. Up to 40 amps whenever the engine is running. Our trips usually involve a lot of driving, sometimes at night when solar doesn’t seem to work very well, so I needed something I could depend on more.

I have had a off the wall idea for somebody that sets up the camper then spends part of most days out and about in the TV. How mush power does the camper use while you're out? I would think a small battery could handle that for a week or so. Now mount another battery, big enough to handle normal loads for a couple of days on the TV. Driving would keep that battery charged, just hook to camper when get back. Might need to switch batteries if don't move often enough to keep trailer charged...

BurbMan wrote:

Gdetrailer wrote:
Often 10 cu ft "apartment size" are good choice because they typically have the lowest draw and best insulation.. The one I have has a name plate draw of 1.1A for the compressor and 1.6A defrost draw.

That's 1.1a @ 120v...at 12v that's 11a. My old 3-way absorption fridge used about 15a on 12v for the heating element. One of the reasons I replaced it with a 2-way that I just run on propane.

The new 12v compressor fridges are good for some applications, but are still challenging for boondocking without a generator. just like a 120v residential fridge. Solar is great, but you're dependent on the weather, a cloudy day will kill your production. In my TC, there's just isn't enough real estate on the roof for 400w of panels.

I believe that eventually absorption fridges will become obsolete but the tech just isn't there yet.

Remember that marine is not apples-to-apples....1) propane is not allowed below deck; 2) any boat big enough to have a fridge has a generator; and 3) you don't stay in one spot on the water like you do in a CG.

I’ve said to myself numerous times that when my 3-way Dometic fridge poops out on me I’ll replace it with a 12-volt compressor model, or maybe find a compressor conversion kit for it. I’ve had very good luck with a small 12v portable compressor unit that was very reasonably priced, so my confidence in them is pretty high.

My propane fridge keeps soldiering on though, and it’s performance continues to surprise me. I just turned it on yesterday in preparation for a trip, and it was down to minimum temps in about four hours in LP mode. Of course our ambients we’re in the 50’s at the time, but still.

Aside from all the normal preventative maintenance they require, I’ve found that one of the most important items that should be checked is the LP pressure. It doesn’t have to fall off very much before it has an effect on the fridge in LP mode. I check mine at least annually now.

I don’t have solar panels right now, although I could add some now that I have a DC-DC charger that has a solar input. I may add some someday, but for now taking advantage of the charging potential available while driving was a better fit for our traveling and camping style. Up to 40 amps whenever the engine is running. Our trips usually involve a lot of driving, sometimes at night when solar doesn’t seem to work very well, so I needed something I could depend on more.

Our stationary power needs are typically low enough that occasional use of a 1000 watt generator will suffice, and I’m sure a modest solar system would as well. But, I prefer shady spots to full sun so I suspect I’d still have at least occasional need for a generator, especially if I were to add a 12v fridge to the mix.

:):)

Gdetrailer wrote:
Often 10 cu ft "apartment size" are good choice because they typically have the lowest draw and best insulation.. The one I have has a name plate draw of 1.1A for the compressor and 1.6A defrost draw.

That's 1.1a @ 120v...at 12v that's 11a. My old 3-way absorption fridge used about 15a on 12v for the heating element. One of the reasons I replaced it with a 2-way that I just run on propane.

The new 12v compressor fridges are good for some applications, but are still challenging for boondocking without a generator. just like a 120v residential fridge. Solar is great, but you're dependent on the weather, a cloudy day will kill your production. In my TC, there's just isn't enough real estate on the roof for 400w of panels.

I believe that eventually absorption fridges will become obsolete but the tech just isn't there yet.

Remember that marine is not apples-to-apples....1) propane is not allowed below deck; 2) any boat big enough to have a fridge has a generator; and 3) you don't stay in one spot on the water like you do in a CG.