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Is a 12-volt compressor refrigerator best for me in my RV?

Hi, Dave,
While attending an RV show recently, I noticed some units have a Furrion battery-operated refrigerator. Do you recommend the battery-only power source? Thanks. —Norman, Looking for a new RV

Hi, Norman,
The best RV refrigerator for you depends on how you plan to RV, as everyone is different. For years the absorption refrigerator, which heats a solution of ammonia, hydrogen, sodium chromate, and water in the burner vessel, has been the standard. It can run on 120-volt power with a heating element, or liquid propane (LP) for boondocking or dry camping.

This operation is done through the cooling unit pictured here. In my opinion, it has gotten some unjust negative press. When the solution is heated, it creates a vapor and rises inside the burner tube to the evaporator coil behind the freezer. There is a chemical reaction that I won’t go in depth with; however, the components form back to a liquid state and need to zigzag back down the tubes to do the entire process again. If the unit is out of level, the liquid can pool on one side and start to overheat, flake, and eventually block the operation.

Parking on slanted driveways not good for some RV refrigerators

Many owners park their units in the driveway prior to heading out on a trip, plug the unit in to get the RV refrigerator cold, pack, and then head out. The trouble with that is most driveways are slanted for runoff and typically more than the 6 percent limit stated by both Norcold and Dometic. So there has been a rash of cooling unit failures or inefficient cooling during hot weather. The campground fiction, as I call it, blames the absorption method and folks rushed to residential fridges.

The challenge with this type of refrigerator is you need 120-volt power, either from the shoreline or generator, or an inverter with a very large battery bank. If you don’t do much or any dry camping, which means you do not have a 120-volt power source, the residential version is fine.

12-volt DC refrigerators

Along comes the 12-volt compressor-driven models which run on power from the batteries and not through the inverter, such as the Everchill or Furrion. Mike Sokol did a test on a Dometic DMC4101 and was very impressed.

It seems in several of his tests, the Danfoss compressor is the key.

Recently, Dave Helgeson posted an article comparing the different models, as well. Dave is the leading expert in all things boondocking.

Need more info to answer the question

As you can see, it is not an easy question to answer unless we know more about what battery capacity you have, solar charging abilities, and how much you dry camp. According to Mike’s article on 12-volt refrigerators vs. 120-volt models running through an inverter, the 12-volt models run much more efficient and draw less battery power. Seems the inverter is the weak link here.

If you have traditional 12-volt lead acid or AGM batteries you only get 50 percent usage and won’t be able to run the 120 volt through an inverter or the 12-volt models very long before needing to recharge. If you have lithium batteries and solar charging, you will last much longer and the 12-volt model would be a good choice.

Again, this all depends on how much dry camping you will be doing.


 You might also enjoy this from Dave 

Can I run my RV’s refrigerator on 12 volts while driving?

Dear Dave,
Can’t I run my RV’s refrigerator on 12 volts while running down the highway and turn off my propane tanks completely? —Fil Patrick Peterson

Read Dave’s answer.


Dave Solberg is a leading expert in the RV industry and the author of the “RV Handbook.”

Read more from Dave here

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Steve Hericks
15 days ago

Not all compressor refrigerators have the same efficiency. Just as variable speed compressors have revolutionized the A/C industry, the same effect results in refrigerators. Domestic, Norcold and Furrion all offer 10CF DC compressor refrigerators that consume about 1100Wh/day. While these are definitely far more efficient than any absorbtion, they are not high efficiency in the realm of compressor fridges. I have a Blomberg 11.4CF, 2 speed, 120V compressors fridge that consumes 746Wh/day and with inverter losses, that becomes about 940Wh/day making my 15% larger fridge about 15% MORE energy efficient than these DC compressor fridges. See my video on YouTube.com/WorkingOnExploring.

Steve Hericks
15 days ago

What is not said but important to understand is that compressor systems are about 8x more efficient than absorption systems. It’s basic physics. Said another way, if an absorbtion fridge runs on 400W of energy, most of it being supplied as heat by burning propane, a compressor refrigerator of the same size can operate on 50W of electricity. The only way absorbtion makes sense is because a tremendous amount of energy is available inexpensively, in a small, light weight container in the form of propane (49.6 MJ/kg). Storing a similar amount of electricity requires a much larger, heavier and expensive storage medium. A lithium ion battery stores .7MJ/kg or about 1/70th the energy per pound.

Left Coast Geek
15 days ago

I replaced a broken Dometic RMD8555 where the parts were unobtainable with a Norcold N2175, exact fit, DC compressor fridge. I have 2 206AH lithium batts replacing my original dual golf cart batts, and I can go like 2 weeks without sun or power (except, if its the two of us, we usually need to dump the holding tanks after a full week or so).. I upgraded my power center for lithium, and upgraded my solar from a 160W PWM setup to 360W MPPT. This fridge/freezer rocks. the freezer stays in the 0-10F range even in very hot weather, and the fridge stays in the 34-38F range. It does humm a little when its cycling, but its at the opposite end of the trailer from the bed, and I can barely hear it, the overhead Maxxfan on low makes more noise. This is in a 21 foot Escape fiberglass trailer.

Robert
15 days ago

We switched from an absorption refrigerator to a 12-volt compressor style in our class B van. One thing I don’t like about the compressor fridge is that it makes a faint, but noticeable, buzzing sound when it runs. The old refrigerator was completely silent. Overall, no longer needing to worry about keeping the van level is a big win, and I’d do it again.

Leonard
15 days ago

The Norcold or “No Cold” absorption fridge was what I got on my 2020 Montana 5’er. After about 1.5 years of traveling the propane feeder tube broke and the whole back of the fridge caught fire. I did get the fire out without RV damage however the fridge was toast. I had JC Refrigeration in Shipshewana, Indiana convert it to a 12V residential. The BEST upgrade I have done! Now the fridge and freezer work flawlessly and I can actually buy Ice Cream again!
I don’t believe that the absorption fridge’s get a bad rap, as fridge fires are one of the leading causes of RV fires. I have 4 x 6V AGM batteries, so I am all good with whatever type of RV I choose. Just MHO.

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