Rethinking Refrigerator

[TomC]

A few weeks back, I was convinced that the refrigerator that I was going to use would be the Summit FFBF280W, which is a 13.8 cu/ft.  It stands 75" tall, 27" wide, and 24" deep.  Has self defrosting (would put a switch in), is Energy Wise, and consumes an average of 440kw/year (that works out to be 50 watts per hour @ 120vac or about 5 amps per hour of 12vdc through the inverter).  The disadvantage is that it really isn't made for travelling. I'm sure the freon lines aren't properly supported (which isn't critical in a house), the shelves do not have ledges on them (could use spring loaded rods), has a protruding door handle, no means by which to secure the door while travelling, would have to drill the case to hold it in place from moving, the condenser is on the rear of the refrigerator requiring special thought as to cooling ducts.  The cost-about $1,100.00

The other choice that I'm now leaning towards is the NovaKool RFU9000 straight 12vdc using a Danfoss compressor and is 9.1cu/ft.  While it isn't self defrosting, it has a differently designed evaporator then our Norcold (that we have to defrost once a week in summer) that I think would make defrosting more along the lines of every two weeks.  Advantages-it is built for travelling and has a front flange that screws to the cabinetry and a positive latch on the door.  The condenser is on the bottom front venting with a fan making it a truly built in refrigerator.  It has ledges on the shelves to hold food in.  It consumes 5.5 amps when running-based on 50% run time, that works out to be 2.8 amps/hour @ 12vdc.  Disadvantage-is smaller and costs $1,800.00.  Opinions?  Good Luck, TomC

[robertglines1]

have used home refrig in last three conversions no problems...actually have 3 in 89 .One in kitchen apartment size,one behind driver dorm size and another dorm size in entertainment bay..so you don't have to go inside for refreshment..The reason for two inside is when the slide comes in the refrig is against island..so we keep a small one for drinks and sandwich meat (Insulin for wife)..haven't yet but could go to Lowe's and replace if needed...15 yrs no problem just let exhaust operate like in a house...once they are cool they don't run very often...Bob. P.S. our camping life style is plugged in shore power or for the rare occasion we are not we are on gen set..can buy a lot of fuel for price differance...

[luvrbus]

Wise choice Tom now you don't need to run the generator for hours to charge your batteries every day when parked those units with the house type drive me crazy in a camp ground running the generator for long periods so the fridge will work during the night.
I have a 100# 12/110 v Norcold chest freezer and it will run for ever on a battery


good luck

[bevans6]

They look a good unit, designed for marine applications.  They have dual voltage units available, DC and AC (actually 12vdc, 24vdc, or 10 to 45 vdc which could be handy for someone, and the AC is 100 - 240 volt, 50/60 hz, which makes it sound like a little switching power supply AC - DC adaptor).  Would it make any sense for you to get a dual voltage unit, so that you could run it directly from shore/generator power, or are you thinking you can simply run it from 12 vdc, via the charger if on shore power so why spend extra for another converter inside the fridge?

Edit:  call it 70 amps a day, you could run it for 3 - 4 days from a 500 AH bank without going too deep into discharge (assumes little other 12v use, which probably isn't the case), you probably have a  big charger so you could replenish that daily use with an hour or two of either gen time or truck driving time if you charge the battery bank from your truck alternator.  I don't see a problem so far...

Brian

[Sean]

I sent my vote to Tom by PM some time ago, but just to get it on record here, I, too, favor the NovaKool.

We have the smaller RF7500 unit and it has been trouble-free for over six years; sips current at less than 2 amps (24 volts) when it's running.  We only defrost every couple months or so; I'm sure it would be more efficient if I kept up with it more frequently.

The plastic door latch handles have broken once off due to flexing, and NovaKool sent us free replacements with no questions asked.

My only recommendation is that after you get it, you add the LED indicator to the Danfoss control so you can tell what's going on with it.  Due to timing issues, our fridge goes into temporary LBCO before the genny starts, and the blinking LED is often our first indication that the batteries are low.

We fit everything we need for two weeks or so (our boondocking limit anyway due to tankage) in the 7.5 cubic foot model, and keep it all secure, by judicious use of baskets:
http://ourodyssey.blogspot.com/2007/08/small-space-saturday-making-most-of.html

Among the many benefits of using a DC powered fridge are:

• Can turn the inverter off when not needed for other things.
• Can use smaller and cheaper MSW inverter rather than the true sine wave required for a fridge, unless you plan to run air conditioners from it.
• Avoids the ~10% "inverter penalty" when running from batteries or solar.

No question, though, that there is a price to be paid for this.  A cheap household fridge plus a cheap sine wave inverter to run it can be had for half the cost.

-Sean
http://OurOdyssey.BlogSpot.com

[Geoff]

I've been running an 10cf, 120v apartment stainless steel Sanyo for 7 -8 years in my conversion.  It stays plugged in all the time and keeps the beer cold while in the RV garage.  When traveling it runs off my inverter or generator.  Never a problem.  I would never spend the money for a troublesome RV refer.

[bebackbus]

I bought a Norcold Marine refer for about $1100 @ west marine.  It runs on 12 volt 24 volt or 110. It uses 2.2 amps on 24 volt or 3.2 on 12volt.  I wired it direct to the house batteries so need for the inverter.

I had a lot of issues with a rv refer.

I've had it for 5 or 6 years works great. I like it most because I never worry about being level.

We are fulltime and use it from AZ to AK.

[happycamperbrat]

When I lived in my prior motorhome I had a Dometic refer. I LOVED it! It was 3 way and would switch between DC power, shore power or propane. I sold it years ago and am now going to have to consider replacement. I really like the convienince of having the 3 way, but I dont like that I have to cut a hole in my bus roof for another one and the house refers are so energy efficient these days that I am not sure (I have to do more study on this) but I think that with the defrost disabled they are as or more efficient then the rv types. At least that is what I have been hearing.

Edit: It wouldnt be too hard to build straps into the wall for traveling with a house refer, though it might be unsightly.

[bevans6]

I have to say that I won't buy another RV fridge either. I will get a marine targetted fridge, compressor running off 24 volts with a 120 option of some sort.

No more waking up in the middle of the night to reset the "No flame" error on the propane for me...

Brian

[kyle4501]

If the road vibrations are so bad that you are concerned about breaking the lines in a household fridge - you may have more serious issues to be dealt with. 
(I wouldn't want to spend much time on anything that vibrated that bad, well, maybe 15 minutes or so. . .  .)

I'm not much of a fan of having ammonia in the camper (- The first owner of my Airstream was in the rear bedroom when the dometic propane fridge leaked the ammonia into the camper - he came close to dying & the resultant lung scaring eventually did him in).

If finances allow, the marine unit with a DC powered compressor is the nicest way to go.

For the budget conscious, a household unit that requires manual defrosting is the least expensive unit. You can add more insulation to the sides & door for longer off time & if you have the condenser coils on the back, you can space those further away from the box & add more insulation there too. Add some muffin fans to enhance air flow over the coils when it is running. . . .
If you modify your fridge useage, you may find that you can go a long time without running the genny & still maintain acceptable temperatures inside the fridge.

[steve wardwell]

we lived with a full size Norcold in a boat for 8 years, twin voltage and found them to be JUST OK. We could not keep really cold items such as icecream during the summers...Although the fridge was adequate we would see temps in the mid  to upper 40s and had to be careful not to load with too many warm items at once. As a result we added a muffin fan, 12 v. and it helped somewhat but did not cure....  We also had a Norcold metal chest type (the biggest of the toploaders) and found this to be a much colder unit and could run down to 10-12 deg. and we used that as the deep freezer..............................In our coach we have a standard 2 door  Amana and love it..for what its worth................s.............

[bevans6]

Can someone who knows how do things set up a poll for fridge selection?  Way off topic of TomC's choice now, maybe a new thread?

Brian

[Kevin Warnock]

I have a NovaKool and it's great.

One project I have in mind for my RTS conversion is to install the fridge horizontally under the countertop, which would be hinged. The benefit is the cold air won't fall out when I open the door. This should result in much less energy use overall. A NovaKool engineer suggested this idea to me by phone when I asked about their separate product to convert your own cabinet into a refrigerator. I had told him I have a full NovaKook fridge already, and he said to just use it on its side. He said I would have to turn the compressor 90 degrees so it remained pointed up. He said the lines are flexible enough I could just unbolt and bend the lines and re-bolt it, presumably to a bracket I would make. He was quite serious about this suggestion, and said it would work well.

I got the inspiration to do this from the many web articles about people converting chest freezers to chest refrigerators. The benefit is the cold air doesn't fall out when you open the door. The low energy use of such a chest refrigerator is said to be simply astonishing - better than any front door refrigerator at any price.

Kevin

[ruthi]

We have a regular full size house fridge that has traveled hundreds of thousands of miles over the last 15 yrs. Never a problem, still going...............

[Iceni John]

I got the inspiration to do this from the many web articles about people converting chest freezers to chest refrigerators. The benefit is the cold air doesn't fall out when you open the door. The low energy use of such a chest refrigerator is said to be simply astonishing - better than any front door refrigerator at any price.

Great minds think alike!   On Sean's recent posting about who uses what types of fridges, I posted my ideas for exactly this setup in my bus.   The more I think about it, the more sense it makes.   My goal is self-sufficiency, using PV panels for all my electrical needs, so big expensive power-hungry fridges simply won't work for me.

John