If you boondock a lot . . .

[DonTom]

Can't do a poll here?

Anyway, my question is . . .

If you boondock a lot . . . Would you consider a NEW RV with a 12 Volt ONLY refrigerator?

-Don- Reno, NV

 

[phil-t]

I don't have any experience with a 12V only frig. Just the little cooler types that we use in the rear of our car. I know our MH frig, on propane uses 12VDC for burner ignition and lights.

 

[DonTom]

I know our MH frig, on propane uses 12VDC for burner ignition and lights.

Yeah, but at just at a small fraction of an amp. The 12V only refrigerators can draw 8 amps when running and that is what they are putting in a lot of newer RVs. I can see many advantages of such, until boondocking for a few days.

-Don- Reno, NV

 

[TonyL]

Last year we did around 80 nights without hookup. We don't have a 12volt fridge but a residential unit that requires 120 volts either by hookup or from an inverter which takes power from the batteries.
We use 4 size 31 lead acid batteries, have a total of 360 watts of solar and ran the generator in the evening from around 8 till 10 when there was no solar gain. By the morning our battery voltage was never less than 12.4.
Hope this helps.

 

[phil-t]

Interesting few threads going here on 12V refrigeration.
Tony, that info is good to hear by me. We are about to take onership of a MH with inverter, residential fridge and some solar (don't know how much right now). I am looking forward to no more safety concerns over the lp frig.
Been reading about the 12V units and they seem to be a big part of the future for RVs.

 

[Pgh_AL]

Im in the process of installing a Dometic in my mh LP/110 . I wish I'd waited a while longer . After hearing all these different opinions about which is which . Now Im confused as all get out .

I've already purchased it a week ago to day. Spent all day last Saturday just getting it in my coach. I've heard more con's than pro's about my new refrigerator . Confused !

 

[phil-t]

So, how about the good and bad comparing 12VDC to 120VAC Refrigerators? The 120V units need an inverter and the loose some efficiency in the inverter? The 12VDC units will run off the converter when on shore power?

 

[solarman]

Can't do a poll here?

Anyway, my question is . . .

If you boondock a lot . . . Would you consider a NEW RV with a 12 Volt ONLY refrigerator?

-Don- Reno, NV

probably not, a propane fridge with a few fan mods has worked for us without issue for years. personally, I see no reason to change just yet. If I had no choice then I would have to consider the extra power load and how to mitigate that. I have no more room on the roof for additional panels, so I either take the hit on autonomy or use an extra portable set.

 

[Mark_K5LXP]

I'd never had an absorption fridge until I got my class A a few years ago. Reading online about all the potential issues had me wondering if I should just cut and run, and go with a compressor fridge. After a few seasons now with it, I find it works pretty darn good once you understand it's limitations. I like that it's completely silent and while it may not be able to keep ice cream rock hard like a compressor fridge can I've never had the freezer not freeze or the fridge get too warm even in 100F temps outside. That's not to say some folks haven't had those problems and maybe some models are better than others. It's hard to beat the convenience of turning it on and letting it go, and not sweating the battery meter every day. Failure of the cooling unit is a concern but I guess you just cross that bridge when you get to it. Meanwhile I see no need to replace my absorption fridge, especially when faced with the process of installing a new solar system and large battery bank to feed a compressor fridge.

Mark B.
Albuquerque, NM

 

[solarman]

Here some panel wattage numbers to give you an idea of the extra load..

12V @8 Amps = 96 Watts, if the fridge is running at say 50% duty cycle then the daily
watt/hour value is 96 * 24 * 50/100 = 1152 W
and say location is mid west in winter with useful sun hours of 4hrs
then panel size is approx. 1152 * 1.5 / 4 = 432 Watts..

ouch !

just a thought.. that's possibly an artificially high duty cycle, it's likely that real usage could be closer to 25% DC
so reducing panels to approx. 220 W

 

[solarman]

So, how about the good and bad comparing 12VDC to 120VAC Refrigerators? The 120V units need an inverter and the loose some efficiency in the inverter? The 12VDC units will run off the converter when on shore power?

for the same amount of heat transfer then clearly the 120V solution is worse just based on inverter efficiency..

 

[TonyL]

Is the fridge 12 volt or 120 volt?
I can only confirm my real world experience. I will admit that we were naive when we purchased the unit not realising exactly what a residential fridge was. Once we bought it, we knew a generator was more of a necessity, and managed reasonably well until I fitted the 200 watt solar panel and second pair of batteries.
We no longer fear camping without hookup.

 

[DonTom]

12V @8 Amps = 96 Watts,

A 12V battery that is at 12.0 volts is pretty near being a dead battery.

12.7V times 8 amps=102 watts. But I assume that 8 amps is off when the refrigerator/freezer gets to temp and there is some duty cycle that is dependent on ambient temp. But if 100F outside, perhaps on full time.

I have NO experience with such non-propane refrigerators, so I am trying to learn about them and see if it is something I want to avoid or not.

I realize the modern DC refrigerators probably also have some small advantages, but conserving energy probably won't be one of them.

At least I won't have to worry about my refrigerator when I run out of propane (that almost happened to me in New Mexico--I don't think they sell propane at any gas stations there and it was on a holiday).

Mark, how do propane sales work there? Is it possible to buy at night or on a holiday in NM?

-Don- Reno, NV

 

[Dreamsend]

My Norcold absorption fridge has worked extremely well and I like the propane option. Mine was made after all the safety recall stuff. On balance, I determined that the propane use risk was lower than a lot of other stuff associated with this lifestyle. Literally millions of hours of fridge usage in all those RVs without mishaps.

If I ever have to get another unit, pretty sure it will be a propane/120 V (or propane/12V if there ever is such a thing). I do a mix of CG power and solar boondocking. Even on highest setting (warmest), everything, including ice cream is rock solid frozen and even fridge compartment stays between 34 and 38 degrees even in 100 degree temps and sun beating on that side of the TT. On 120 V without shore power, it eats amps - found that out by forgetting to switch to propane one travel day. Used about 35 amps per hour - that's inverting of course, by the time the low batt alarm went off.

Linda

 

[Pgh_AL]

Well what i got from this is that it depends on what kind of camping or boon docking / dry docking you do .

So for what i have planned the refrigerator I have will fit my life style and meet my expectations . I will be mostly dd and bd . So i will continue with the installation of my Dometic 2862 LP/ 110 and make the best of it

 

[DonTom]

Well what i got from this is that it depends on what kind of camping or boon docking / dry docking you do .

Yep. I guess it's NBD if I run the generator enough. But in my old junky RV listed below, with a 300 AH lith battery and propane refrigerator, it won't be all that often and for long (80 Amp lith converter) that I need to.

Why can't they make new RVs like that, even if the cost is several thousand more? Perhaps making a different type of RV for those who mostly boondock and those who stay mostly at RV parks will be a good answer.

At a full hookup RV park, solar, generators propane refrigerators and lith batteries and inverters are useless. And even in route none of such stuff should be needed when boondocked overnight (maybe the 4KW inverter to run the MW oven would be useful, however). And 12 volt refrigerators would be no problem. In fact, all advantages, IMO.

For being boondocked often for more than a week straight probably should have a different type of RV designed. Will also be more expensive. Then all that stuff is very important.

-Don- Reno, NV

 

[solarman]

A 12V battery that is at 12.0 volts is pretty near being a dead battery.

12.7V times 8 amps=102 watts. But I assume that 8 amps is off when the refrigerator/freezer gets to temp and there is some duty cycle that is dependent on ambient temp. But if 100F outside, perhaps on full time.

it's industry standard practice to use nominal voltages hence 12 or 24 or 48 and not 12.4 or 13.2 or some other arbitrary value.

normally an EE would not use amps either, we always use Watts until the voltage or amperage is required or known.

DIY joe will always use amps as you make an assumption that voltage is always 12 V

 

[solarman]

Why can't they make new RVs like that, even if the cost is several thousand more? Perhaps making a different type of RV for those who mostly boondock and those who stay mostly at RV parks will be a good answer.

"they" do, my Outdoors RV 24rks is a prime example..

 

[Pgh_AL]

Yep. I guess it's NBD if I run the generator enough. But in my old junky RV listed below, with a 300 AH lith battery and propane refrigerator, it won't be all that often and for long (80 Amp lith converter) that I need to.

Why can't they make new RVs like that, even if the cost is several thousand more? Perhaps making a different type of RV for those who mostly boondock and those who stay mostly at RV parks will be a good answer.

At a full hookup RV park, solar, generators propane refrigerators and lith batteries and inverters are useless. And even in route none of such stuff should be needed when boondocked overnight (maybe the 4KW inverter to run the MW oven would be useful, however). And 12 volt refrigerators would be no problem. In fact, all advantages, IMO.

For being boondocked often for more than a week straight probably should have a different type of RV designed. Will also be more expensive. Then all that stuff is very important.

-Don- Reno, NV

The way i see it and the way I've been using my rig so far . I would only have to run my gen for maybe 30 minutes every 24 hrs . And id still have refrigerator full of cold food and beverages . That works for me

 

[Mark_K5LXP]

A 12V battery that is at 12.0 volts is pretty near being a dead battery.

Not in active use. 12.0V during discharge is about 75% SOC, 10.5V is empty.

Mark, how do propane sales work there? Is it possible to buy at night or on a holiday in NM?

Honestly I've never tried. Most places only have the 20lb tank exchange stands, but I've never had a problem getting the RV tank filled during at a few service companies around ABQ. I tend to use a quick lube outfit a mile or so from my house but there are a few around that are in and out during normal business hours. Even the Costco's here will fill RV propane. I fill so infrequently I haven't thought about a late night or "emergency" fill. Last year I tested my extend a stay setup using a grill tank just to see how it worked, and I made it 3 days running off grid with high furnace use in November. I figure worst case I could always pick up a 20lb tank at a grocery store, gas station or hardware place if I needed to until I could get the main tank filled.

Mark B.
Albuquerque, NM