Low energy DC refrigerators - Fiberglass RV


Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-01-2012, 05:44 PM   #1
Senior Member
 
Name: Kevin (Ken)
Trailer: Bigfoot 17, 1988
Wisconsin
Posts: 159
Low energy DC refrigerators

I'm surprised there isn't more about these new Danfoss compressor freezer/refrigerators on Fiberglass RV. I visited a friend off-grid who had an 80qt model recently and it was amazing. Beers were partially frozen in no time, and the thing was only drawing 2 or 3 amps. It goes down to -8 degrees F.

I want to get a 43qt Edgestar:

Amazon.com: 43 Qt Portable Compact Refrigerator Freezer - EdgeStar: Kitchen & Dining

However, I am living in a city for the next few months and drive by places to buy cheap ice all the time, plus I have a nice Igloo cooler that fits well inside the old fridge just right, giving me additional non-refrigerated storage and double insulation for the cooler.

I could always rig up a slide-out option, but what I am considering is to continue using ice, keeping the Edgestar outboard, but using it periodically to make the ice. I could take it out of the back of the truck, fill it full of ice cube trays or block trays, blast it for a few hours to make a few days worth of ice, then put it away. This way I can use my own highly filtered water to make the ice, no fridge motor noise in the trailer, and in the end use only a tiny fraction of the energy that even the low draw Edgestar would use, if I used it continuously as a refrigerator. In fact, with solar panels, the refrigeration might actually become free, since you could always make your ice when it is sunny, using otherwise wasted surface charge to do it...

Also, going DC means none of the hazards of running propane while driving, or the well known hazard of old propane fridges setting the trailer on fire.

Seems like a boondocker's dream, but I don't think people really know about these things yet.
__________________

__________________
pindraak is offline   Reply With Quote
Old 11-01-2012, 07:00 PM   #2
Senior Member
 
David Tilston's Avatar
 
Name: Dave W
Trailer: Trillium 4500 - 1977, 1978 (2), 1300 - 1977, 1973, and a 1972
Alberta
Posts: 5,317
Registry
For those that have all electric trailers, compressors fridges are the only option. I think that using ice out of one to cool your ice box is a false economy. All the energy required to cool the inside of the fridge itself is wasted. As handy as your ice box may be, just replace it with the fridge. The compressor will shut down when the fridge is cool enough. If it is too noisy at night, shut it off and the ice in the freezer will keep it cool
__________________

__________________
David Tilston is offline   Reply With Quote
Old 11-01-2012, 07:00 PM   #3
Senior Member
 
Carol H's Avatar
 
Name: Carol
Trailer: 22' Airstream Formerly 16' Scamp
British Columbia
Posts: 11,731
Registry
Ken these have been talked about a few times here before. They are an interesting unit but for me the dream is to have a working fridge while boondocking that uses 0 amps. As such a fridge that runs on propane is much preferred. As far as safety and propane goes there are a lot of folks that use propane and very few accidents. The key is to have your system check frequently to ensure it is safe. I dont run the fridge on propane while driving - just put some ice packs in it and keep it closed as you would a cooler - if in real hot areas & long drive I will switch it to DC but the tow can try to keep up with consumption of power at last in part.
Carol H is offline   Reply With Quote
Old 11-01-2012, 07:25 PM   #4
Senior Member
 
Name: Steve
Trailer: Bigfoot, Trillium, Scamp 5th Wheel
Spokane Wa. and Las Vegas, Nv.
Posts: 1,312
Registry
The DC setting on a 3 way fridge is, at best, meant as a stop-gap. On the other hand A 12v compressor is incredibly efficient and so quiet you will have to strain to see if you can hear it. Personally I love 12v fridges. I had a front opening style and other than small it was far superior to my propane fridges. You don't have to level them and being mechanical they should run forever. If you have even a small solar system it should produce more than enough energy to keep you running forever. The one thing I don't like is chest style fridges. Unfortunately, at this point it is far easier to find chest style 12v fridges than front door styles. I don't want to live out of an ice chest!
__________________
Steve Hammel is offline   Reply With Quote
Old 11-01-2012, 07:37 PM   #5
Senior Member
 
Name: Kevin (Ken)
Trailer: Bigfoot 17, 1988
Wisconsin
Posts: 159
David: you seem to have missed the part about making ice during the day on surface solar charge that would otherwise go unused. I will basically be using ice as a battery that takes advantage of free solar my lead acid batteries can't. I think the ice will amount to no additional cost to what I'll be doing anyway.

I can see the point about energy wasted on cooling the refrigerator, but it might be partly cancelled out by having an extra-insulated cooler. The max amps the Danfoss units use is around 5 or 6 amps - I think this draw for a few hours every 3 days would amount to less than 1ah draw avg over 36, which could not be significantly more than running it constantly. My cooler in the fridge setup now only uses about 10lbs ice every 3 days.

The main reason not to install the refrigerator is that the only reasonably priced ones come in top-open form, which would necessitate an awkward sliding drawer sort of installation, as opposed to the cooler plus storage space setup I have now, plus there are the expenses and hassles of customizing the space and installing it. I already spent 6 months of full time plus labor working on this Bigfoot.

Another reason is that if you use it as a refrigerator, you have to choose between fridge and freezer. If you choose fridge, as most would, then you have to buy ice for drinks, or take everything out periodically to make your own ice, which means going through all the regular hassles of my plan and then some anyway.
__________________
pindraak is offline   Reply With Quote
Old 11-01-2012, 07:41 PM   #6
Senior Member
 
Name: Kevin (Ken)
Trailer: Bigfoot 17, 1988
Wisconsin
Posts: 159
Carol: If you have solar, the dc as an intermittent icemaker will use the equivalent of zero amps. Moreover, after startup costs, refrigeration will be free. I can't see propane as any sort of boondockers or off-grid dream because you have to keep buying propane all the time, amounting to constant expenses and dependency on petroleum companies, distribution networks, etc...

As far as the safety of old propane units, the issue is not about leaks, assuming the avg RV tech is even competent enough to check for that. It's not about propane starting the fire, it's about hot metal in parts of the fridge system setting the surrounding wood of your trailer on fire. It's only a matter of time with an old unit and some configurations of surrounding wood. If you are driving or otherwise not in the trailer when it happens, so that you can stop it right away... whereas low e dc or an icebox has little or no fire risk at all.
__________________
pindraak is offline   Reply With Quote
Old 11-01-2012, 07:44 PM   #7
Senior Member
 
Name: Kevin (Ken)
Trailer: Bigfoot 17, 1988
Wisconsin
Posts: 159
Steve: you should consider getting used to the chest style, because it is far more efficient. Every time you open the door on a vertical fridge you are wasting a substantial amount of energy by dumping out all the cold air and having to start over, whereas a horizontal unit barely even needs a door. Ever notice how the horizontal freezers in the grocery store don't have lids?
__________________
pindraak is offline   Reply With Quote
Old 11-01-2012, 08:30 PM   #8
Senior Member
 
Name: Steve
Trailer: Bigfoot, Trillium, Scamp 5th Wheel
Spokane Wa. and Las Vegas, Nv.
Posts: 1,312
Registry
Maybe if they invented a drawer style that would fit in the space where a standard fridge goes but until then I need to make the best use of small space more than saving a bit on energy.
__________________
Steve Hammel is offline   Reply With Quote
Old 11-01-2012, 08:52 PM   #9
Senior Member
 
Name: Kevin (Ken)
Trailer: Bigfoot 17, 1988
Wisconsin
Posts: 159
I agree that would be ideal. I'm not too crazy about doing it that way in my trailer either, with the ones available, partly because they are not the right shape, which is what got me started on the icemaking option. I forgot that everyone here is thinking in terms of highly mobile trailers, as I also think of my trailer as a temporary building for off-grid living, which makes putting the cooler in another building or outside an option - particularly efficient for colder weather.
__________________
pindraak is offline   Reply With Quote
Old 11-02-2012, 12:13 AM   #10
Senior Member
 
David B.'s Avatar
 
Name: Dave & Paula Brown
Trailer: Lil Snoozy
Arizona
Posts: 1,723
Registry
Ken, we purchased a Novakool DC 2600 12volt upright refrigerator/freezer (2.4 CU ft.) from Backwoods Solar Electric Systems Inc., for our 13' Scamp to replace our Dometic 3 way refrigerator/freezer. The "footprint" is only slightly smaller, but the inside is so much roomier, the cooling time is immediate (important here in Arizona), it can handle angles of 30 degrees (it is used in many boats), is very very quiet, and our 100 watt solar panel let us camp off the grid continuously for 6 weeks as we traveled up the west coast (Monterey Ca. to Seattle Wa.).
Hope this helps you with your dilemma.
Happy Trails
Dave & Paula
__________________
David B. is online now   Reply With Quote
Old 11-02-2012, 05:04 AM   #11
Senior Member
 
Name: Steve
Trailer: Bigfoot, Trillium, Scamp 5th Wheel
Spokane Wa. and Las Vegas, Nv.
Posts: 1,312
Registry
"Ken, we purchased a Novakool DC 2600 12volt upright refrigerator/freezer (2.4 CU ft.) from Backwoods Solar Electric Systems Inc., for our 13' Scamp to replace our Dometic 3 way refrigerator/freezer. The "footprint" is only slightly smaller, but the inside is so much roomier, the cooling time is immediate (important here in Arizona), it can handle angles of 30 degrees (it is used in many boats), is very very quiet, and our 100 watt solar panel let us camp off the grid continuously for 6 weeks as we traveled up the west coast (Monterey Ca. to Seattle Wa.).
Hope this helps you with your dilemma."

I had a very similar experience only w/o solar. I had a Norcold/Thetford 2.4 cu ft. with a beat up old 12 volt in temperate weather and easily got 2-3 days before a recharge. If I had solar it wouldn't have ever needed recharging, just maintenance. The working cycle was rare once it was cold.
__________________
Steve Hammel is offline   Reply With Quote
Old 11-02-2012, 07:42 AM   #12
Senior Member
 
Name: Mike
Trailer: 1984 13' UHaul
Louisiana
Posts: 543
Registry
I have a Whynter 85 qt. The same company (Chinese) makes the Edgestar. They advertise 2.75A draw on 12V. It is actually a 5.3 A draw on 12V. (2.75A @ 24V). I still like mine. It is very effecient and quiet and I have enough solar Amps to run it forever on 12V.
The best is Engel - they are also the most $. They make a door type (not chest type) 60 qt. for around $700.
There are also fridge/freezer chest types (two different compartments) that can be bought. I don't see a need for a freezer since I'm only boodocking for maybe a week at most.
For the money, I like the Whynter/Edgestar.
If money were no matter. Engel is by far the better Fridge.
I haven't research or tried the Novakool, but reports on this site do make it appealing!
__________________
itlives is offline   Reply With Quote
Old 11-02-2012, 09:51 AM   #13
Senior Member
 
Bob Miller's Avatar
 
Name: Bob
Trailer: 1973 Hunter Compact II
California
Posts: 7,912
Sorta to head off any scares, in about 40+ years of RV'ing I have never heard of a fire that started in a LP refrigerator that was properly installed in an RV.

I know of one that caught fire after a DIY'er installed a new one and didn't check for leaks, but that's about it.
__________________
Bob Miller is offline   Reply With Quote
Old 11-02-2012, 09:54 AM   #14
Senior Member
 
mmeyer's Avatar
 
Name: Michael J
Trailer: U-Haul VT
Indiana
Posts: 472
Registry
Ken: I have been using the concept you mentioned for the last 3 years when we camp at the NPS campground on Ocracoke NC. I use a 50qt ARB fridge freezer and a 50qt Yeti cooler. The ARB uses the BD35 variable speed compressor on 12 Volts, I have 150 watts of solar 50 permanent and 100 portable and 210 AH or battery bank using 2 trojan 6V golf cart batteries. I monitor with a NASA BM-1 battery monitor system. I typically freeze 18 500ml water bottles before we leave. I run the ARB as a freezer and swap out 6 bottles of ice each day in the Yeti refreezing the water i pulled out. We keep shrimp, fish and meat in the freezer along with 10# of ice for drinks. Worked fine for the first two seasons and my experiment was cut short last week by Sandy but all was going well.
I can tell you my movie nights with the inverter TV and DVD player put more of a dent in the bank than I thought but even then I never have gotten below 60% reserve in the morning.
Typically by 10 AM I am adding to the bank with the freezer running and it continues till about 4PM. this is for late Oct. In the Spring when we go back I get longer charge cycles as the sun is higher and out longer. The freezer is not protected with anything but the optional cover.
I spent about 6 months researching Engle, ARB and the Chinese variants and after looking at all the refrigeration curves and tables and Austrailan comparisons decided on the ARB. If money was no option I would go with the National Luna from South Africa. It has much more insulation and is built like a tank for about 3x the $. all except the Engle use the Danfoss Compressor. When you go above 50qt it puts you into the BD50 compressor which means about 50-70% more amps. Also the Chinese always market the amps at 24V to make them look good gotta read the fine print.
The bottom line is your theory works in the real world and i am very happy with my ARB
Michael J.
__________________

__________________
mmeyer is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Casita refrigerators--need to know Betty L. Problem Solving | Owners Helping Owners 1 06-28-2012 07:01 AM
12v fridge wirh low energy consumption? Mouse Problem Solving | Owners Helping Owners 4 06-06-2012 02:37 PM
Gas Absorbtion Refrigerators Lisa H. Problem Solving | Owners Helping Owners 19 06-27-2008 11:28 AM
Help with older model refrigerators Phillip Krueger Problem Solving | Owners Helping Owners 3 06-11-2007 10:53 PM
Casita Refrigerators Lisa M. Problem Solving | Owners Helping Owners 6 05-22-2007 01:28 AM

» Upcoming Events
No events scheduled in
the next 465 days.
» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 08:01 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.