Portable 12V Fridge Review
We review five ways to keep food fresh and drinks cold on your next journey
Images and Text Courtesy of Overland Journal, Summer 2007 Edition.
Just how many soggy sandwiches have you endured in your lifetime? If you go camping often and use an ice chest, chances are the answer is, “More than I care to count.” Few things are more disappointing than returning to camp late in the afternoon after a vigorous hike, looking forward to that extra sandwich left over from lunchtime, only to find your mayonnaise jar floating in a watery sea of miniature icebergs. And there’s the sandwich in its plastic baggie, pinned down under the beer bottles. As you pull out each dripping item, with pinky finger in the air and a wince on your face, you see that the mayo is now a gruesome mixture of floaty white stuff, and the fluffy sandwich bread has been reduced to soggy dough.
Enter the 12V portable fridge, which never needs ice. No more soggy food, no more tepid four-day-old Coke—everything stays clean and dry and maintained at the precise temperature you select. You can even keep ice cream frozen. While fridges are significantly heavier than ice chests, the difference is minor once you factor in the weight of ice. And although the interior of a fridge seems small at first glance, not only do you save the room the ice would consume, but you can reload the fridge with each day’s soft drinks and beer to chill, rather than having to keep your entire stock in there. The fridges reviewed here will hold anywhere from a week to two weeks worth of fresh food for a couple.
These very attractive conveniences do come with a price though: You can buy a lot of ice for thsoe cost of a fridge. And if you frequently camp for a couple days in one spot, you’ll need to consider a dual-battery system or solar to ensure adequate power to both the fridge and the vehicle’s starting circuit. Still, once you take the plunge there’s little chance you’ll ever look back. I was like a giddy little kid on the first trip I took with my own fridge, pulling out frosty drinks and fresh meals for days on end, never thinking twice about ice. There is a deep sense of personal satisfaction when you are camped on a remote Mexican beach with your friends, and despite the fact that you haven’t seen a town in days, much less a store with ice, you still have cold cervezas to share. It’s almost as good as cheating death. I now consider myself a “12V-fridge enthusiast,” however geeky that may sound. As far as I am concerned, a fridge ranks right up there with a competent suspension, protective hardware, and good tires as a priority vehicle modification. Fridge or a winch? I’d take the fridge any day.
There are three common types of portable fridges on the market. Least expensive—and least effective—are thermoelectric units. These are actually more cooler than fridge, as they do not use any type of refrigerant, and are capable of only a limited chilling range below ambient temperature. They are also electrically inefficient, and do not lend themselves to use with a stationary vehicle where battery capacity is an issue. Another type of portable fridge is the absorption unit, typically found in RVs. These are not recommended for overland vehicles that will be driven on rough trails and subject to vibration, bumps, and off-level surfaces. They typically use an ammonia-based cooling system that must be heated, and the nature of the design requires them to be operated on level and stable surfaces. In contrast, the fridges we tested for this review all use a heavy duty compressor and a sealed refrigerant system to chill their contents. They combine low amperage draw with true refrigerating and even freezing capability, and can be expected to operate properly for years even in hostile conditions. We chose five currently available models, and evaluated them for construction, performance, convenience, and price. All are of more or less similar interior volume—between 39 and 47.5 quarts—and are considered mid-size units. Other models from these manufacturers range from a picnic-oriented 16 quarts to a 100-quart monster that rivals the hold of a fishing trawler. Special thanks goes to Jeremy and Windy Edgar for their assistance with the physical evaluations and setting up the photo shoot for this article.
ARB MT45F-AL (42 qt.)
ARB is a well-established and respected name in the portable fridge market. Their most recent models have been improved with quieter, more efficient motors, and each now incorporates a built-in digital thermometer on the control panel, allowing the user to monitor the temperature inside the chest.
Construction consists of a melamine-coated steel shell, polyurethane insulation, and an ABS plastic interior. A single control dial turns the unit on or off and adjusts the temperature settings, numbered “zero” to “five.” This one-piece control makes operation simple, especially nice if you need to turn the unit on or adjust the thermostat while driving or in the dark. No visual confirmation is necessary. The digital thermometer is powered by a small internal battery.
The ARB’s lid pivots on two open-ended pin-style hinges, and can be removed easily when opened and slid to one side. This can be considered a blessing or a curse, depending on personal preference. While it makes removal of the lid effortless for cleaning and fully loading or unloading the fridge, it can also come off inadvertently if bumped, and clatter to the floor. A simple capture device on one hinge would be a worthwhile addition as standard equipment; however, a hinge-lock accessory can be ARB MT45F-AL (42 qt.) purchased from Engel. I would also like an option to hinge the lid along its length, since with the fixed hinge location on the short side, the height requirement to open it is increased.
Molded into the top surface of the lid are two circular depressions vaguely resembling cup holders, and one large rectangular depression perhaps intended to be a tray of sorts. They are so shallow that I am convinced they are more for decoration than function. I would prefer a flat surface that could be used as an impromptu desk or tabletop. (Structurally, the depressions do serve to strengthen the lid.)
The interior includes a full-size, removable, epoxy-coated wire basket, and a removable vinyl-rubber floor mat that makes cleaning the bottom of the cabinet easier. The lid closure consists of a single, plated steel, spring-loaded hasp, which does a good job of keeping the lid closed on rough roads. The carrying handles are tubular steel, pressed flat on the ends and drilled to accept the four screws that fasten each to the short sides of the cabinet. The handles can be inverted to adjust their height, or simply removed. Ours is shown with the handles mounted in the “down” position. There are two removable power cords supplied, one for “shore power” (120VAC), and one for battery power (12VDC). The 12VDC cord includes a fuse carrier with a 10-amp fuse.
Thermostat dial and digital thermometer.
Shallow depressions in the lid are supposed to be a tray and cup holders, but really serve to strengthen the surface.
• Time-proven reliability and excellent reputation. • Good value.
• Low power consumption.
• Quiet operation.
• Full-size basket makes loading/unloading easy.
• Easily controlled without visual input (singledial operation).
• Integral digital thermometer.
• Many accessories available.
• Painted exterior is susceptible to scratches and subsequent rust if abused.
• Thin steel exterior around motor compartment is easily dented.
• Removable hinge system can be problematic. (a hinge-lock accessory is available)
• Lid only opens in one direction, limiting mounting configurations.
• Cup holders and tray are not deep enough to be practical. A flat surface would be preferred.
• Replacement of thermometer battery requires disassembly of cabinet.
• Thermometer only reads in Celsius.
FridgeFreeze 45-Liter (47.5 quart)
Based in California, FridgeFreeze is a more recent player in the recreational refrigeration scene, garnering press reviews several years ago as a unique product. It remains so to this day. The FridgeFreeze is arguably the stoutest and best-looking unit of the bunch, boasting hand-built construction and high-quality materials and finish. Being bulletproof and beautiful comes at a price, however, as this is the most expensive and heaviest model in the review.
A Danfoss BD35-F compressor is at the heart of the cooling system, with an optional rubberized toggle switch on the control panel that switches the compressor from low to high speed for boosted cooling. Thermostat selection is via a rotary knob with settings from “off ” to “one” through “seven,” seven being the coldest. A green lamp on the panel indicates if the unit is powered. There is also a built-in digital thermometer cleverly powered by a tiny solar panel—no battery required. A 14-amp fuse is located on the 12VDC power cord, and two fuses for 12VDC and 120VAC are located behind a louvered access panel on the cabinet. The 12VDC power cord utilizes a twist-lock connector at the fridge side, located high up on the face of the control panel. I really like this type of connector, which is very reliable at staying plugged in, but easily removable for transport.
The top rim, control panel, and lid are made of smooth, white, gelcoated fiberglass with the FridgeFreeze logo in the center. Stainless-steel hardware adorns the brushed, diamond-plate, marine-grade aluminum cabinet. (A smooth finish is also available.) A stainless-steel draw latch secures the lid, with a tab that accepts a padlock. A continuous, stainlesssteel piano hinge spans almost the full length of the lid. A groove in the underside of the lid captures a thick, wide bulb-seal that keeps the interior airtight. A braided tether cable prevents the lid from being opened too far. Attached to the underside of the lid are two plastiic C-clamps that hold a rubberized flashlight used to illuminate the fridge at night. While this is a thoughtful feature, I would probably remove it, as it encroaches on valuable storage space in the top of the cabinet.
The aluminum exterior serves as the condenser for the cooling system. Consequently, there is no cooling fan and the sides can get quite hot. (I took a spot measurement using an infrared thermometer during a long running cycle and got a surface reading of 116ºF.) The bottom corners rest on heavy-duty, non-marring, molded plastic feet. The handles are large aluminum tubes secured to thick aluminum brackets on the short walls of the cabinet. The manufacturer’s data claims they are tested to 1,000 lbs. The interior of the chest is smooth aluminum, save for a small plate that houses the temperature sensor in one of the upper corners. Caulking seals the seam where the sidewalls meet the bottom floor panel. A small, removable, epoxy-coated white wire basket can be suspended from the top rim to hold produce or smaller, more delicate items. A twopiece plastic divider is also included. This divider is meant to be placed horizontally inside the chest to isolate colder items on the bottom and create a slightly warmer area above. The two pieces are linked together and have finger holes so that either half can be flipped up to access items below. One of the greatest attributes of this fridge is the insulation, which is 2 3/8 to 3-inch-thick, high-grade polyurethane foam.
Control panel and electrical plug outlets.
Supplied flashlight can be seen mounted to open lid.
Stainless steel hinge and drop-in basket shown.
A folding divider creates a dual-zone chest.
Chest can hold 53 of these cans (56 without the flashlight and clamps).
Integral thermometer with small solar panel.
Latch mechanism can accept a padlock.
Danfoss BD35-F compressor, as seen inside the FridgeFreeze
12VDC cord with twist-lock connector.
• Beautiful construction.
• Hand-built with high-quality materials and craftsmanship.
• Excellent insulation properties.
• Exterior is highly corrosion-resistant and durable.
• Easily controlled without visual input (single-dial operation with toggle switch).
• Integral thermometer.
• Extra long 12VDC power cord.
• Exterior colors stay cooler in sunlight.
• Exterior walls are used as a heat sink and can get hot to the touch, so require more clearance around them.
• Power cords plug in at the control panel (top of unit) which detracts from the tidy appearance.
• Cool-down time is fairly slow.
• The horizontal divider plates are tight-fitting, with sharp edges that can scratch the interior aluminum surface.
• Thermometer shuts off at night or in the dark (no solar power).
• 12V power cord does not include cigarette lighter connection.
National Luna NLR-40 (42 quart)
Based in South Africa, National Luna is a smaller company with a hands-on approach to product development. Popular in Africa since the late 1990s, National Luna fridges are only now becoming available in the U.S.
The NLR-40 uses a Danfoss BD35-F compressor coupled with an intelligent control module that allows for the most user input of all the fridges we reviewed. The user interface is a touch-button panel coupled to an illuminated red LED digital display. A thermometer reading is visible when the display is not being used for input. Adjustable parameters include target temperature, differential temperatures, low and high temperature alarms, probe offset (temperature corrections for thermometer accuracy), defrost modes, and Celsius or Fahrenheit units. In addition to the control panel, there is a selector switch for an “auto” setting to maximize power savings, or a “manual” setting to maximize and accelerate the unit’s cooling power. Despite the vast array of user controls, I was disappointed to find no power switch. The only way to turn the unit on and off is by connecting or disconnecting the power cord from the power source. As such, you will need to consider adding your own switch.
This fridge takes full advantage of the variable-speed compressor, and it is a powerhouse at rapid cooling. Target temperatures are available well below 0°F, and input power can be either 220VAC, 115VAC, 24VDC, or 12VDC. The controller has an automatic speed function that can sense when surplus power is available, such as when shore power is applied or when the vehicle’s engine is running, and increase the cooling capability. A fuse housing is mounted on the control panel for easy access. The panel has six colored indicator lamps for “fuse blown,” “fault code,” “reverse polarity,” “220V,” “12V,” and “power.”
The exterior is a hammer-textured surface of color-bonded aluminum that surrounds 2 3/8” thick high-density foam insulation. A very rugged black plastic is used for trim and mounting hardware, including the hinges and corners. Hinges consist of two separate pieces at each corner, secured with stainless steel screws. The rim of the cabinet and the inside of the lid are constructed of molded plastic. A vinyl rubber bulb seal keeps the chest air tight. The lid is secured with a stainless-steel draw latch that accepts a padlock. There is no tether cable, so care should be taken not to over-extend the lid. Carry handles are mounted to the short sides, and have roller grips and springs to keep them folded down when not in use. The 12VDC power cord is permanently attached to the bottom of the cabinet, which is nice for ensuring a good connection, but can be annoying when you want to isolate the unit from power or transport it. I would prefer a twist-lock type of connector. There is an auxiliary power outlet meant for DC appliances to be plugged in and powered externally, but the outlet is an African-style connector and is not compatible in North America. Perhaps a NA version could be retrofitted. Available accessories include a floor mounting plate and a soft cover.
The interior of the chest is split-level, with a shelf area over the compressor compartment. The lining is smooth aluminum sheeting with caulked seams. A stainless-steel wire basket with removable plastic handles fits into the shelf area of the chest. The underside of the lid is equipped with a clear plastic cover, which houses a light for nighttime illumination.
Hinge detail. Power supply to convenience lamp is visible.
Latch mechanism can accept a padlock.
Auxilary outlet (African-style plug) and hard-wired 12VDC connection.
Underside of lid and drop-in basket shown
Chest holds 50 of these cans.
Stainless handles are spring-loaded and have roller grips.
Convenience lamp built into lid.
• Handsome looks.
• Sturdy construction.
• Extremely fast cool-down capability.
• Digital controller allows extensive user input.
• Convenient fuse location.
• Automatically works with varying power sources from 12VDC to 220VAC.
• Auxiliary power port allows external accessories to be plugged in (African-style plug required).
• Spring-loaded handles fold flat, saving cargo room.
• No on/off switch
• Control panel is located at bottom corner of unit, making it difficult to see unless the unit is mounted to a slide, or arranged such that there is nothing blocking access to the panel.
• Temperature adjustments require visual input to see what level is currently selected (unlike a dial where you can estimate the level by feel).
• 12VDC cable is permanently attached to the unit, making it inconvenient to transport or isolate from the power source if it is directly connected to the battery.
• Exterior shell is susceptible to dents.
Waeco CoolFreeze CF-40 (39 quart)
Waeco is another manufacturer that has enjoyed years of popularity among recreational users worldwide. A large company recently bought by Dometic, their CoolFreeze fridge is one of the many different electronics products they produce for the leisure market.
The CF-40 uses a Danfoss BD35-F compressor, controlled with a power management panel recessed flush into the top edge of the cabinet. This is a smooth-surfaced touch-panel with color-coded controls and indicator lights for easy viewing and operation. The thermostat control utilizes a single button pressed repeatedly to cycle through seven temperature levels (“cold” to “freeze”). There is a power on/off button and “Turbo” button that will increase the output of the compressor (at the expense of greater power consumption) for faster cooling. There are three indicator lamps for “power,” “turbo,” and “error.” A three-position switch near the bottom of the cabinet acts as a battery monitor and shuts off the power at any of three set points (10.4V, 11.4V, or 12V) depending on preference. If the thermostat control panel fails, an emergency switch can be turned on that will run the compressor full-time.
The cabinet is made entirely of high-impact polypropylene plastic filled with polyurethane insulation; the lid is made of polyethylene plastic. Even the handles are made of heavy-duty plastic. The obvious advantage to this construction is that it is impervious to corrosion and rust and weighs less than steel, and in fact the Waeco is the lightest fridge in the group. It is also easy to clean, and doesn’t dent easily. The exterior finish is handsome, molded in two shades of grey with a bold white “Waeco” logo emblazoned across the front. The lid hinges on two pivoting pins that are molded right into the lid itself. The pins rotate inside barrels molded into the plastic body of the cabinet, eliminating any metal parts or fasteners. The hinge barrels are duplicated on both long sides of the cabinet, so the lid can easily be removed and repositioned to open from the other side if desired. A nylon tether cord with plastic tabs (also reversible) keeps the lid from opening too far. The lid closure has no hardware save for a spring inside the latch, and is molded right into the lid and body. Small plastic tabs with catch teeth hook into openings on the top rim. To open, you grip the handle and lift outward , releasing the teeth from the catches. A thin ridge of plastic surrounds the top surface of the rim, providing a locating perimeter for a thin foam gasket seal recessed into the lid. Much like the ARB and Engel, the Waeco has cup holders molded into the top of the lid. However the depth is a bit more substantial, so they are useful rather than merely cosmetic.
The interior is similar to the National Luna in that it has a deep main compartment with a shelf over the compressor housing. However, in the Waeco the shelf is a bin, with a wall partially dividing it from the main compartment. Thus the bin shares the refrigerated air but at a warmer temperature than the large compartment. Testing revealed this differential to be anywhere from 10 to 20 degrees. The entire interior is plastic; the main bin has a white-walled surface covering the evaporator plates. A full-size epoxycoated wire basket fits the main bin and includes a drop-in divider that sections off a third of the basket on either end. According to the Waeco global website, the newest version of the CoolFreeze line is now available with an interior light, a digital thermometer, and an up/down button selector for thermostat adjustment, with display units that can be set to read Celsius or Fahrenheit.
Touch-button control panel.
Small compartment and drop-in basket shown.
Cup holder detail.
Formed plastic hinge barrels are open-ended so lid is easily removed.
Holds 49 of these cans.
Plastic/Nylon tether detail.
• Easy to clean (including the smooth control panel).
• Will not dent easily; corrosion-proof.
• Reversible lid mounting.
• Turbo option for faster cooling.
• Adjustable power interrupt settings depending on battery monitoring preferences.
• Emergency run switch (backup in case thermostat fails).
• Full-size basket makes loading/unloading easy.
• Sturdy, wide handles are comfortable and easily removed if needed.
• Auxiliary bin is convenient for items you don’t want as chilled as those in the main compartment.
• Built-in plastic hardware would be difficult or impossible to repair if damaged.
• Lid seal consists of a very thin strip of foam gasket attached to a thin ridge of plastic.
• No thermometer on model tested (newest models have them).
• Temperature adjustments require visual confirmation to see what level is currently selected.
• Dark-colored lid collects solar heat.
I wanted the performance evaluations of these fridges to be as consistent and repeatable as possible, while simulating actual field conditions. I debated using constant AC power stepped down to 12VDC, but decided instead to employ deep-cycle batteries, as would be the situation in a vehicle. I used a pair of brand new Deka group 31 AGM deep-cycle batteries, load-tested to verify their condition prior to use, for most of the performance tests.
I consulted with a friend and fellow overlander, Rob Wyatt, who is an electrical engineer. An accomplished traveler who owns a couple of fantastic overland campers, Rob was enthusiastic about the project. He built a fine circuit board complete with a USB data-logging device that could capture and send real-time data to my laptop. There it was recorded, viewed and analyzed with a software program. The device was designed to accommodate two separate circuits with two deep-cycle batteries, allowing two sets of data to be recorded at once. This allowed me to run a simultaneous comparison of two fridges, which worked great when it came to verifying that the ARB and Engel were indeed essentially the same. The data captured included voltage, amperage and temperature. The fridges were placed in a thermostatically controlled test room with an average ambient temperature of 80°F and an average relative humidity between 12 and 16 percent. The data log sample rate was 0.76hz (one sample every 1.32 seconds.)
1. The Race
I conducted a speed test, using only battery power, whereby each fridge began at ambient temperature, completely empty, and was given a time allowance to see how cold it would get. In other words, which one can cool itself the fastest? The ARB and Engel fridges, with their patented swing motor, have only one selector dial, with no further power options available to the user. Therefore these units would have to rely on their sensible design parameters (meant to balance power consumption with cooling capacity) to be competitive. The remaining contenders, using the Danfoss compressors, all had high/ low power selectors in addition to the standard thermostat controls, allowing the user to override the usual compressor speed in favor of boosted power.
Since I’ve owned an older, Freon-cooled, 60-liter swing-motor fridge for many years, I knew that the design had impressive cooling capacity. However, based on prior reviews I’d read, and the imposing appearance of the Fridge- Freeze, I was sure it would be the hot rod of the group. So I was stunned when the understated National Luna, running side by side with the hulking FridgeFreeze, simply blew the lid off its rival. Allowed 45 minutes to run at full power, the interior temperature of the FridgeFreeze dropped 43°F from its starting ambient.
Meanwhile the interior of the National Luna plummeted to 68° below ambient. Further testing revealed the mettle of the budget-priced Waeco, which practically tied the National Luna at 67° below ambient—a mere single-digit difference. Obviously the National Luna and Waeco designers have fully exploited the variable-speed capability of the Danfoss compressor. Their selection of control modules capable of “turbo” modes, coupled with good fan and evaporator designs, seems to have paid off. Meanwhile, the separated-at-birth swing-motor fridges performed more on a par with the FridgeFreeze, cooling their interiors to an identical 38° below ambient. While not as astonishing as the two top performers, this is still an impressive achievement. Assuming an outside temperature of 80 degrees, in less than an hour any of these fridges will have chilled its interior to a true refrigerator-like 42° or lower.
2. The Workhorse Test
The obvious progression from the first test was to see how the fridges would compare when loaded with some thermal mass. This would create a real chore for each unit, since removing warmth stored in liquid is much more energy-intensive than removing it from air. Would there be a steadily declining curve in temperature? Or would it be a lopsided bell-curve?
I again ran this test using battery power, to simulate real-world conditions. For thermal mass, I used a popular Irish beverage that comes in a dark-colored 14.9-ounce can emblazoned with a golden logo (any guesses?). I loaded 16 cans (totaling 238.4 ounces) in each fridge, and cranked every power selector to its maximum.
Once again the National Luna sprinted past the field, taking 2 hours and 44 minutes to chill nearly two gallons of liquid to 29°—50° below the starting ambient—on battery power alone. This result was far beyond any other—second this time was the FridgeFreeze, which took three hours and 57 minutes to achieve the same 50° drop. Oddly, the Waeco, which had almost equaled the National Luna during the cool-down race while empty, took six hours and 18 minutes. And the ARB/Engel duo had managed a 42° drop at the end of six hours and 48 minutes, when I stopped the test.
3. The Warm-up
All of these fridges use polyurethane foam insulation. Not only the density and thickness of the insulation must be considered, but the insulation qualities of the materials that encase it. To test the relative effectiveness between models, I shut off each unit with its contents at a stable refrigerated temperature, then recorded the rise in temperature over time. The FridgeFreeze, thanks to its generous use of insulation material, scored best here, with a rise of just 20.2° in two hours. Second was the Waeco at 22.7°, followed by the National Luna at 23°, with the ARB/Engel scoring a near-identical 32.2° and 33.2° respectively.
4. Glutton or Miser?
All of this impressive cooling capacity is fantastic, but at what cost to the power supply? The results from testing the average amperage draw of each unit are useful in determining what effect each model will have on a battery. First we’ll examine the results obtained during the workhorse test, when each unit contained a stock of cans. Note that this was while the motor ran constantly (which all of the fridges did during the workhorse test.) Not surprisingly, the least cold fridge (ARB/Engel) had the lowest power consumption, drawing an average of only 2.60 amps. Second lowest was the FridgeFreeze, at 4.70 amps, followed by the Waeco at 5.05 amps. Predictably, the fastest fridge of the group, the National Luna, used a battery-melting average of 5.75 amps. However, keep in mind that the National Luna only had to run for 2 hours and 44 minutes to achieve its target temperature, compared to almost four hours for the FridgeFreeze. If left to cycle for the same period, the National Luna would average only approximately 1.8 amps. Essentially, the contents in the National Luna cooled 31 percent faster for 1 amp less on average.
Maintenance cycles were also tested for average power consumption. Each unit was measured after a temperature between 28ºF and 32ºF was reached and the compressor went into a cycling mode, operating intermittently to maintain the setpoint on the thermostat. A sample duration of one hour and 40 minutes was measured. The ARB/Engel units were on par with the National Luna as the lowest consumers, at only 1.75 amps average. The FridgeFreeze was next at 2.25 amps, and the Waeco was last using an average of 2.75 amps. This would translate to the following amp-hour consumption for a 24-hour period: 42ah (ARB/Engel, National Luna), 54ah (FridgeFreeze), and 66ah (Waeco).
All of the fridges have a spike in amperage draw when they are first turned on to get the motor moving. This is interesting to note, as it gives us an idea of how much stress the electronic circuitry endures (albeit briefly.) By increasing our sampling rate to 30hz (30 times per second) and taking multiple readings, we measured the following spikes: ARB/Engel: 8.13 amps; FridgeFreeze: 9.00 amps; National Luna: 10.00 amps; Waeco: 9.52 amps.
5. Noise levels
All of these fridges are very quiet. We placed a decibel meter six inches from the compressor location of each cabinet, and recorded the following results: ARB/Engel: 50db; Waeco: 50db (turbo and non-turbo); National Luna: 51db (manual and automatic); FridgeFreeze: 52/54db (low/high compressor speed).
Overland Journal used Deka group 31 deepcycle AGM batteries to power the fridges for our test and review. Deka’s AGM (absorbed glass mat) design is completely sealed and requires no maintenance. The electrolyte is absorbed in sponge-like separators made of matted glass fibers, which allows them to withstand the rigors of overland use better than traditional lead plate construction. The Deka batteries are VRLA (valve-regulated lead acid), and use a recombination action to prevent the escape of gasses normally lost in a flooded lead-acid battery. Through-partition weld seals are used to ensure the highest quality protection against minute electrical currents which could otherwise flow between cells, contributing to self-discharge. Terminals and bushings are completely solid forged components with no porosity, unlike typical cast units which are porous and can leak corrosive gasses. Standard terminal connectors as well as threaded studs are included, and custom terminal configurations are available via special order.
Each unit is encased in a rugged polypropylene case manufactured and controlled exclusively at an on-site molding facility (not outsourced). The Deka group 31 size is well-suited to an overland/ expedition vehicle, as it is a good compromise between weight and capacity, while offering exceptional value. Rated at 105 amp-hours (20Hr rate) and 800CCA, they offer many hours of fridge power while stationary at a campsite or trailhead. And just in case the situation arises, they will operate while submerged in up to 30 feet of water. Deka batteries are made in the U.S. by East Penn Mfg. Co., Inc. Visit them on the web at eastpenn-deka.com.
National Luna, The powerhouse from South Africa
There is no denying the rock-solid history behind the ARB and Engel products. Since the 1960s they have accompanied countless expeditions around the world. Attractively priced, reliable, and supremely durable, they are justifiably popular (I own the 60-liter Norcold version.) Many retailers carry them, and many accessories are available. Thus either makes sense for someone with an average budget who wants to buy into the proven performance of the brands. No doubt the patented swing-motor is one of the fundamental reasons for the renowned status of this fridge. It has only one moving part and its own suspension system, so even the worst corrugated roads have no effect on it. I once ran a swing-motor compressor on a battery that dropped below 11 volts. While cooling capacity was severely limited, the fridge did not shut off and suffered no damage. Three of us on the Overland Journal staff have been using these fridges for years (including both ARB and Engel). We estimate well over 100,000 miles of cumulative abuse, and they still work as if new. Their resistance to vibration and heat, along with their resilience to being packed in an overloaded cargo area, are truly legendary.
The FridgeFreeze is a work of art, and would be as much at home on a fine yacht as in an overland vehicle. With a handsome design and top-ofthe- line craftsmanship and materials, it is also the largest and heaviest of the group. There are some benefits to the heft, as it boasted the largest capacity and best insulation, so it should perform admirably at maintaining a stock of cold items at a multi-day camp. Better insulation also means less work for the electrics. This would be a great fridge to pair with a solar electric system.
The bottom line for me? I want something that will survive the type of trips I take and get the job done when it comes to cooling my goods down quickly and keeping them that way. Beyond that, convenience, looks, and cost can be considered and factored into the decision, but play a lesser role.
I narrowed my choice down to the Waeco and National Luna. As someone who tends to travel light, I appreciate the lightweight construction of the Waeco, and the fact that it will not dent or rust. I think the updated control panel and integrated thermometer on the newest models will make it even better. The part of the Waeco that gives me some pause is the lid. While I like the fact that it is reversible, I am leery of the plastic pin hinge system and the plastic cooler-style closure. I’m also not impressed with the lid seal, especially compared to the burly, commercial-grade bulb seal on the FridgeFreeze. It is a very thin foam gasket that rests on a raised edge molded into the rim of the chest. The foam is not very substantial, and I expect that the raised edge on the plastic could suffer nicks or chips over time, reducing the effectiveness of the seal. If I owned this fridge I’d keep an extra gasket on hand. Despite my reservations about the lid, the Waeco has superb cooling capacity, and its insulation is second only to the FridgeFreeze. The battery-management options and emergency-run switch are smart features that round out an excellent value for the money.
In the end, the National Luna was my top choice. I was so impressed with its performance that I actually got excited thinking about putting it to some severe testing out in the desert. Power efficiency is a good thing, but in my opinion, the option to kick the fridge into high gear and get your stuff colder, faster, is even better. A lot of my local excursions are spur-of-the-moment, and it’s nice to be able to turn the fridge on when you leave the driveway and know that by the time you get up on the mountain or out to the lake, your drinks will be cold and your cold cuts won’t suffer from a lag in cool-down time. Despite the higher amperage draw for initial cool-down, the National Luna is very efficient once it begins cycling in maintenance mode, and as we discovered with our tests, the numbers average out quite nicely.
From a durability standpoint, I am more inclined to trust the newest breed of Danfoss compressors than those of the past, and the National Luna is equipped with such a compressor. The Danfoss BD35-F is hermetically sealed and has a variable drive, meaning that the temperature can not only be regulated by cycling on and off, but by varying the RPM of the motor, increasing efficiency. The latest design features a brushless, permanent-magnet motor that is mounted with a shock-absorbing suspension. It also incorporates safety features such as selective battery discharge limits, and protection against overload and start failure, fan overload, and overheating. These motors are available with a soft-start feature, meaning they no longer require a high start-up speed, thus reducing power draw. They are designed to work with solar power supplies, and have an impressive operating range of 10-45VDC, so they will not suffer damage from being run on a low battery.
In addition to its powerhouse performance, the National Luna is a goodlooking fridge; not too showy, but stout and utilitarian—like a lot of kit from Africa. I also like the digital, touch-button controller that doesn’t dumb-down the capabilities the fridge can offer to the user. The option to run any of four different voltage supplies is a nice feature that will increase the odds of keeping it running on a trip anywhere in the world. (The one change I would make is to add a twist-lock connector where the 12VDC cord enters the cabinet.) The smooth interior is easy to keep clean, and the split-level chest is great for someone like me who likes to keep a small basket of energy bars, fruits, veggies and snacks near the top, where they’re easy to grab and not quite as cold as the Guinness. The National Luna has different exterior finishes available, as well as a transit bag (cover) for protection and extra insulation, and a base plate for semi-permanent mounting. The power controller can be fitted with a battery monitor and low-voltage audible alarm. The National Luna is the standout in a fine group of fridges, and you can expect to see a long-term evaluation of it next year.