Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-07-2008, 09:29 AM   #1
Winnebago Camper
 
Join Date: Apr 2008
Posts: 16
I know some folks need the gas as they boon dock a lot. For many of us it would seem to me that by going to the 12 volt fridge as in boats we could get rid of the following, 1) vent in roof that sometimes leaks, 2) vent in side where bugs & dust comes in, 3)gas line that has to flex if the fridge is in a slide out, 4)ammonia gas that likes to eat itself thru metal to be free, 5)the fire danger that that little flame has when dust & bugs get in the vent. I see Tiffin is going to residential fridg in some models but going threw an inverter seems to defeat saving energy over having a 12 volt compressor in the first place. In all my boats never had a fridge problem but in RVs they seem to have to change them out a lot. The newer 12 volt ones are more efficient. Has anyone replaced a gas with an electric 12 volt one? What are your thoughts?
Art in Mobile is offline   Reply With Quote
Old 11-07-2008, 09:29 AM   #2
Winnebago Camper
 
Join Date: Apr 2008
Posts: 16
I know some folks need the gas as they boon dock a lot. For many of us it would seem to me that by going to the 12 volt fridge as in boats we could get rid of the following, 1) vent in roof that sometimes leaks, 2) vent in side where bugs & dust comes in, 3)gas line that has to flex if the fridge is in a slide out, 4)ammonia gas that likes to eat itself thru metal to be free, 5)the fire danger that that little flame has when dust & bugs get in the vent. I see Tiffin is going to residential fridg in some models but going threw an inverter seems to defeat saving energy over having a 12 volt compressor in the first place. In all my boats never had a fridge problem but in RVs they seem to have to change them out a lot. The newer 12 volt ones are more efficient. Has anyone replaced a gas with an electric 12 volt one? What are your thoughts?
Art in Mobile is offline   Reply With Quote
Old 11-07-2008, 10:29 AM   #3
Winnebago Camper
 
Join Date: Jul 2000
Posts: 8
Art:

I dont think the technology for a LARGE fridge exists. Most of those boat fridges are very small. Our new Monaco has a residential fridge and I would never go back to a propane fridge. With all the recalls and fires I am amazed they are still certified by the AGA. I was told by a senior person at Fleetwood that both Dometic and Norcold were working on some type of hybrid as they are losing sales to residential models. Of course that was before the severe downturn in the MH market. I would guess that more than 50 % of mid to high end units are shipped with residential fridges.
__________________
Moisheh
2008 Dynasty 42' Diamond IV
2009 Silverado Toad
moisheh is offline   Reply With Quote
Old 11-07-2008, 10:31 AM   #4
Winnebago Camper
 
DavidMc's Avatar
 
Join Date: Dec 2002
Location: On-The-Road
Posts: 10
I have done this (replace "standard" RV refrigerator with a "12 volt compressor" version).

Mixed results.

Details of the process with comments were posted on the Escapees forum
Install Experience
duplicated here at iRV2
Install Experience
where there is a link to my photo sequence of the process.

Installing an all electric refrigerator presumes (in my opinion) having a solar system already in place.

Basic idea is good, the implementation by Norcold needs some improvement.
__________________
David

My signature used to include a link to my personal web-site - - - however:
DavidMc is offline   Reply With Quote
Old 11-07-2008, 11:45 AM   #5
Winnebago Master
 
MrTransistor's Avatar
 
Join Date: Jan 2004
Location: Albuquerque, NM
Posts: 504
Ug.....
__________________
Have Fun!! Mark & Donalda 04 Horizon 40WD no TOW 90,900+ miles and counting
Triumph Bonneville & Susuki S40 on the back
MrTransistor is offline   Reply With Quote
Old 11-07-2008, 04:11 PM   #6
Winnebago Master
 
John_Canfield's Avatar
 
Join Date: Jan 2005
Location: Back at the ranch
Posts: 2,041
We can well relate to this! As former blue-water cruising sailors we were sort of stuck with 12V refrigeration due primarily due to cost. For marine use, there were basically two types of refrigeration: 12 volt and holding plate. 12 volt was simply a compressor driven by 12 volts. They were all small and at least as of a few years ago, none of them could support freezer temperatures. The best our well insulated (4" of sprayed foam) box could do was about 30 degrees or so.

Holding plate refrigeration consisted of a rectangular box in the cooler with a solution (freon circulated by a compressor through the solution) that would freeze at a very low temperature. Essentially this was a large, very cold ice block. The compressor could be either engine driven, or 110v operated. It was impractical for that size compressor to be operated by 12V.

As a former cruiser, I was astounded at the ability of ammonia gas refrigeration to get down to 0 to 10 degrees for an effective freezer. On the boat, we could never keep ice cream. One of my first questions about RV refrigeration was "can I keep ice cream?"
__________________
--John

2005 Horizon 40AD, 2005 Jeep Liberty CRD
John_Canfield is offline   Reply With Quote
Old 11-07-2008, 04:53 PM   #7
Winnebago Camper
 
Join Date: Apr 2008
Posts: 16
Yes John I must have my ice cream so I will look very closely at the residential type fridge in my next RV. I was just hoping a break threw would come along in 12 volts without having to use a 12 volt starter motor.
Art in Mobile is offline   Reply With Quote
Old 11-07-2008, 06:00 PM   #8
Winnebago Master
 
smlranger's Avatar
 
Join Date: Sep 2004
Location: Glen Allen, VA
Posts: 2,170
Our next one (if there is one) will have a residential fridge. I guess an auto gen start will be a must and good deep cycle batteries. Adequate solar panels would certainly be a plus.

It has been our experience that you can never fully trust the absorption RV fridge....sometimes your eggs get frozen or something spoils.
__________________
'07 Country Coach Allure 470 Siskiyou Summit #31578, Cummins ISL 425; 2014 Ford F150 toad; Air Force One Toad Brake.
Glen Allen, VA; Smith Mountain Lake, VA.
smlranger is offline   Reply With Quote
Old 11-08-2008, 03:29 AM   #9
Winnebago Master
 
Join Date: Nov 2005
Posts: 1,096
Over ten years ago they were experimenting with thermoacoustic refridgeration using sound waves and helium. The power requirement was similar to that of a walkman type radio.

Check out:

http://www.purdue.edu/uns/html4ever/...au.refrig.html
__________________
Neil V
2001 Winnebago Adventurer WFG35U
NeilV is offline   Reply With Quote
Old 11-08-2008, 05:15 AM   #10
Winnie-Wise
 
Wizard's Avatar
 
Join Date: Mar 2007
Location: Home on the hill in Georgia
Posts: 296
Back in the old days, read 70's, I had a TT with a 3 way fridge/freezer, full size by that years standards. Ran on propane, 12 volt or 120 volt. Worked pretty good, don't know why they stopped making them. Saved a lot of propane while going down the road and sometimes when boondocking. Don't remember who made them but think Dometic.
__________________
Jerry & Patsy Potter, Taz & Jake Jr.
2000 Winnebago Journey
2006 Ford Explorer 4X4
[SIGPIC][/SIGPIC]
Wizard is offline   Reply With Quote
Old 11-08-2008, 05:16 AM   #11
Winnebago Camper
 
Join Date: Jul 2000
Posts: 8
smlranger:
You would be surprised at how energy efficient these fridges have become. We have a huge dbl. door in our Monaco. It has 6- 6 volts and one 110 solar panel. The solar should be much larger to do any good. I have had the unit run about 28 hours on the inverter and the temps in the fridge were still -4/38. But residential fridges are not for everyone. Serious boondockesr would not be happy. We run our genset a few times every 24 hr. period and all is good!
__________________
Moisheh
2008 Dynasty 42' Diamond IV
2009 Silverado Toad
moisheh is offline   Reply With Quote
Old 11-08-2008, 06:53 AM   #12
Winnie-Wise
 
TXiceman's Avatar
 
Join Date: Aug 2000
Location: Full Time, TX Home Base
Posts: 432
Our old 79 trailer has a still working 3-way frig, propane, 120 vac and 12 vdc. So why can't this proven old technology be used again...we call this progress or in accountant talk...make it cheaper.

ken
__________________
Amateur Radio Operator (KE5DFR)|Full-Time! - 2012 6.7L Ford Crew Cab Dually -2013 HitchHiker Champagne 38RLRSB - Travel with one Standard Schnauzer and one small Timneh African Gray Parrot
TXiceman is offline   Reply With Quote
Old 11-08-2008, 09:13 AM   #13
Winnebago Master
 
John_Canfield's Avatar
 
Join Date: Jan 2005
Location: Back at the ranch
Posts: 2,041
Those large 12V fridges/freezers are probably all absorption gas - all you need to do is heat up the ammonia by any means and you have refrigeration. That technology doesn't work in the marine environment due to the requirement of the unit remaining fairly level.

I think there might be some small, portable 110V/12V freezers around, but I don't know how cold the freezers get.

After my earlier post about marine refrigeration, I remembered there was a company making a 12V powered holding plate system, but the motor was good size and drew quite a bit of current. With holding plate refrigeration, you only run the compressor long enough to take the holding plate(s) down to zero or -10 or whatever and then shut the compressor off, so the energy consumption is periodic.
__________________
--John

2005 Horizon 40AD, 2005 Jeep Liberty CRD
John_Canfield is offline   Reply With Quote
Old 11-08-2008, 09:20 AM   #14
Winnebago Owner
 
Gary RVRoamer's Avatar
 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 51
The "old" 12v refrigerator technology still exists and is used in smaller models. It simply adds 12v powered heater that can be used instead of propane as the heating agent - otherwise it is a standard absorption fridge. They don't use it in larger models because the 12v energy consumption is excessive for a large fridge, which requires a heat source in the 600-800 watt range (800 watts @ 12v = a 70 amp draw on your batteries!). Propane is much more efficient and very inexpensive to use.

The largest 3-way fridge in the Dometic line is only 7 cubic feet.
__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is offline   Reply With Quote
Old 11-08-2008, 01:34 PM   #15
Winnebago Watcher
 
Join Date: Feb 2002
Location: Aguanga, CA, USA
Posts: 1
I have been interested in this for several years as well. There are a couple companies making 12v compressor fridges comparable to the double door rv units. Tundra (owned by Dometic) has an 8.5 cu.ft. double door model and NovaKool makes a 9 cu.ft. unit. I suspect that the unit discussed above was a small single-door unit with a little freezer "compartment", which might explain problems with a cold-enough freezer.

I haven't had any experience with either of these, but have with a residential "SunFrost" 12v unit used with 4 solar panels (300 watts) and 2 Trojan T-105 batteries. It worked great, and used the same "Danfoss" compressors used in the Tundra and NovaKool units. (BTW, the SunFrost is extremely bulky and totally unsuitable in an rv.)

Note that the compressor type are much more efficient than absorption types - nearly 10x in fact. I actually measured ("Brand" power consumption meter) the power consumption (on 115v) of my Dometic "New Dimensions" (about 9 cu.ft. I believe) and it uses 5 Kw-Hr/day (outside temp 85 F during day and 60's at night). The Tundra is rated at about 0.65 Kw-Hr/day!

It should make a lot of sense if one has a substantial solar panel system. I have those solar panels on my rv, so if my Dometic ever gives out, I'll probably look seriously at replacing it with the Tundra. It probably would require running heavier wiring for the 12v wiring to the fridge.
jspande is offline   Reply With Quote
Old 11-08-2008, 01:46 PM   #16
Winnebago Owner
 
Join Date: Sep 2005
Posts: 146
Has anyone converted to a residential frig? I looked on line and found that a 18.2 Cubic Foot unit would fit within the opening of my 4 door Norcold. The 18.2 is about 6" deeper than the Norcold but that wouldn't cause too much of a problem. Yea, I would have to put in a sine wave inverter, and an extra battery but that cost with the cost of the 18.2 (around $650.00) would be cheap if you consider that a new Norcold would cost around 3K.

Can anyone think of any other negatives besides the increased 120Volt draw when on shore power. The 18.2 would provide half again more space than the Norcold.

Right now my frig is okay but it is now over 5 years old so I am thinking maybe I should start considering my options if the frig goes belly up.
__________________
Pat Tribbey

2003 Ultimate Advantage
Ptribbey is offline   Reply With Quote
Old 11-08-2008, 03:16 PM   #17
Winnebago Camper
 
DavidMc's Avatar
 
Join Date: Dec 2002
Location: On-The-Road
Posts: 10
A couple points on numbers (from experience):

1. Cost of the Norcold is around $1,200. (a bit less than $3,000).

2. The 12-volt compressor Norcold runs on Less-Than 3.6 amps when the compressor is running.
Compare this 3.6 amps at 12-volts to 0.36 amps at 120-volts (or use the approximate equivalent of 43.2 watts ). These numbers should help you compare/evaluate a residential model.

The 7-cubic-foot version I have runs directly from the 12-volt supply (when no AC is present). No need for an inverter (indeed it would waste energy to use the inverter to run this unit).

Hopefully this helps you decide.
__________________
David

My signature used to include a link to my personal web-site - - - however:
DavidMc is offline   Reply With Quote
Old 11-08-2008, 08:06 PM   #18
Winnebago Master
 
Ray,IN's Avatar
 
Join Date: Aug 2001
Location: North America somewhere
Posts: 695
You may find 12VDC appliances interesting.
__________________
2000 Winnebago Ultimate Freedom USQ40JD, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member,FMCA."We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert the Constitution. "Abraham Lincoln"
Ray,IN is offline   Reply With Quote
Old 11-09-2008, 03:14 AM   #19
Winnebago Camper
 
Bob (WA0MQE)'s Avatar
 
Join Date: Jun 2003
Location: Between Colorado Springs, CO & Fulton, TX
Posts: 20
There's nothing wrong with running your refrigerator on AC with a good inverter and a good battery bank. We travel all the time this way. The engine has a large alternator and I have 230 watts of solar panels that also keep the batteries charged. This way the engine alternator isn't carrying the full recharge to the batteries. Likewise I feel safer then running the refrig on propane while driving, and I don't have to worry about turning off the propane when entering a gas station.

We saw one of Tiffin's motorhome models at a recent RV Show which had the residential style refrig and it looks like a very good idea to me.
Granted this may not be such a great idea if you boondock a lot but with the proper amount of batteries and more solar panels this shouldn't be a problem either.
__________________
Bob 2006 Monaco Camelot 40PDQ
US Navy Carrier Battlegroup 1959/1963
Summer in Colorado, Winter Texas Gulf Coast
Bob (WA0MQE) 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
Rear HVAC compressor will not come on Suncruiser 37F bobder41 Winnebago Class A Motorhomes 7 06-30-2015 10:25 AM
Second Air Conditioning compressor only comes on when plugged into 110 volts, not whe bobpie General Maintenance and Repair 27 10-08-2014 07:13 PM
Norcold Fridge compressor cycling frequently? RanchoVectra Heating, Cooling and Appliances 8 06-26-2007 01:16 AM

» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Winnebago Industries or any of its affiliates. This is an independent, unofficial site.


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 01:03 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×