Are you in the market to buy a new portable fridge
If you’re in the market to buy a new portable fridge, the decision on which choice is getting harder to make. Throwing a few drinks and tucker in an chilled esky ready for that camping weekend, or for even more planned fare for touring weeks on end was pretty much the normal part of any 4WD trip, but now portable fridges have made esky’s almost obsolete.
But why is choosing a fridge getting so confusing for many?
Because every company rolling out a new re-badged or unique portable fridge is under pressure to flood your field of view with glossy brochures, flyers, and every other advertisement, plus throw in a few gimmicky give-always to entice your wallet out of your pocket. Picking a winner is harder than the average Melbourne Cup office sweep.
But the sales banter is right on one thing though, not all fridges are equal and they never will be as long as there are different manufacturers using varying techniques and components to build and test them as well how they determine what they want you to read.
Now most average 4WDs and tourers will of course choose the average size fridge of around 50 litre capacity, unless of course you happen to be married to my wife and need an 80 litre fridge/freezer, a 50 litre freezer for the snags due to my lack of fishing prowess, and maybe an extra 35 litre drinks fridge just in case. Anyway the point being that if we look at the tech specs for this average size 50L fridge as an example you will find a huge variety of results, performance figures and warranties from each maker to inspire you to choose their version.
Let’s look at some common brands most of us can recall.
Many people may straight away say Engel, a portable fridge brand that’s been around longer than most 4WDers. So the fact it’s been around for eons means it must be good right? Well so has the incandescent light bulb, but who goes out of their way to fit old bulbs to a new home nowadays? Others may recall names like Waeco, and they would be right in saying they have new designs and models coming out faster than Apple, but their decision to pursue Asian derived running gear instead of the ever reliable Danfoss is cause for concern in my opinion. Essentially the other end of the spectrum from Engel.
Many portable fridge manufacturers are still using the Danfoss range of compressors, to their credit in my view, and simply slot them into their own specifically design case. However this is where the differences really start to emerge, as variations of insulation material thickness, application, and even case material and component layout changes how the fridge will perform. The insulation is absolutely critical to any fridge performance and the same applies to the little one shoved in the back of your 4WD with the sun glaring through the window to add a little challenge to the compressor.
But when it comes to the ‘performance figures’ some manufacturers dance around how they come up with the reason why theirs is the best. How do they do that, you ask? By creating their own operating environment and conditions to obtain the desired results. Not suggesting any wrong doing as such, but more a case of putting their best foot forward in that proverbial dance I mentioned.
Working in the real world
In some ways it’s a bit like the fuel economy figures you get with a new car, most average drivers simply can’t replicate them in the real world traffic. They would need an almost clinical environment in order to achieve the same results. When it comes to portable fridges some manufacturers may use a 25 degreeC ambient environment in a special testing cabinet, some will use 32 degreesC.
Aside from my being professionally involved in the technical side of most portable fridge manufacturers over many years, this information can also be gleaned from the technical details in brochures or on websites if you care to look for them. But the problem is the outcomes can vary greatly. Along with ambient temperatures during testing, the different manufacturers use varying internal fridge temperatures as well, some only set at 5 degreesC barely enough to keep the Iced Coffee cold. Others may be set in the negative territory, not because they want to really challenge themselves, but because it’s a better option for their test outcome.
Most comparisons buyers and sellers use to gauge performance is current draw, usually expressed in amps per hour. The testing of fridges are generally performed over a 24hour period and the average current draw of the cycling on and off phases are then calculated using an amp-hour accumulator which gives a reading of consumed power. The desired figures then go into the sales brochure for your reading pleasure, stating figures like “only 0.77Amps/hr” etcetera.
Fridges working in the real world
Unfortunately the real world use of a portable fridge will find the ambient temperature it works in generally much higher, especially in the back of a 4WD parked up next to that Outback billabong. As we know you simply can’t leave dogs or kids locked in a car in our searing Australian climate due to the potential of severe over-heating, yet we think nothing of asking that little fridge to keep the beers at a chilly 2degC without skipping a beat.
When you think about it, that 25 degreeC test environment is nowhere near reality. Then of course we will want to regularly reach into the fridge for that chilly beer, or perhaps the kids need some cold water or treats, and every time the lid gets opened and more cold air escapes it requires the compressor to fire up once again.
The more a fridge gets used, the worse it’s performance results will be depending on design, insulation, and compressor start up demands. All of a sudden that 0.77A/h figure is a long way from achievable. So where does that leave the average traveller trying to figure out what is best for their hard-earned dollar.
Well it’s almost impossible to offer a guide without knowing each person’s individual circumstances.
A few tips
I know that sounds like an insurance PDS but here’s a few tips to help you work it out. First, don’t put amp/hours first. Look at the space you need for the sort of trips you enjoy, is that weekend getaways or longer travel adventures. Yes taking beer is important, but not a survival necessity in most circumstances. So work out your food space and drinks space you might normally want.
Simply don’t buy a bigger fridge than you really need regardless of what the brochure says. Some fridges now have multiple size options in one package, so they really offer more advantages than any others for a variety of trips. Look at where you are going to place it in your vehicle, is footprint easier to accommodate than height or vice versa. Where or how will you access it and is the easiest option. Poor access can result in the lid being open longer than necessary, wasting precious energy.
Next, pack the fridge to the brim every time you head out. Yep, right to the top with no gaps. If it’s just a weekend getaway you have planned, fill the bottom of the fridge with bottles of water before putting the bare essentials on top. This way your fridge is not working hard trying to simply chill air. A full fridge is an efficient fridge.
Prepare meals where possible and pre-freeze them in the house freezer in nice square, easy to pack shapes. Doing this takes the workload off the portable fridge, and placing them in when ready replaces warmer air with a cold equivalent of the same space, an instantly better result after closing the lid. Another option to consider is an insulating bag or cover, these can work well, but ensure the condenser has adequate ventilation. This is the section where the compressor resides usually and requires airflow through the fine tubing. Remember a condenser unit is nothing more than a heat exchanger, so poor airflow will result in the fridge working much harder and be less efficient on power consumption.
Next really easy to follow tip is using the ‘drive time’ to make the most of your opportunity to get fridge temperatures lower. Don’t freeze the tomatoes of course, but drop the set temperature when driving along and use the fact the electrical system is all working along harmoniously whilst getting further down the track to the day’s destination. Once you have reached your stop for the day, bring the temperature back up to a level that still keeps your food safe overnight but draws much less power by cycling less often. This will extend your battery time significantly especially if stopping for a few days.
But most importantly, make sure your battery and electrical system is in the best operating condition. The number of times I have seen amateurish electrical systems as the cause of poor fridge performance would astound many. Everything from bad battery selection and maintenance, ordinary management systems and components, poor electrical connections and a lot of inadequate cable sizes are the reason behind more fridge failures than the fridges themselves.
Bad systems will deliver bad fridge performance, full stop.
So when you read back and consider these few tips and considerations, the difference between 0.77A/hr and 0.83A/hr becomes much less of a concern doesn’t it. So many portable fridge salespersons rely heavily on this one small technical element of their fridge credentials. If you find this is the best argument they offer as to why you should buy their fridge, you know they’ve got little else to offer. Keep looking.
So hopefully this has been of some help in understanding more about portable fridges, how they are ‘rated’ and how to select the best one to suit your needs. Then it’s simply up to you to get the best performance out of it regardless of what the brochure states. Enjoy a cold one.