The standard mobile refrigeration in the majority of RVs is a small capacity door fridge/freezer.  It has a small freezer section, not much bigger than a shoe box, that will hold little more than ice trays.  For the long term traveller smaller refrigerators are not sufficient.  Some travellers use a portable chest refrigerator such as an Engel or Waeco which can be placed in the back of the vehicle/4WD as additional fridge/freezer use.

Dometic Australia has released a new 8 series model  refrigerators (R8501 and RML8551) with a removable freezer compartment.  A clip system facilitates quick and simple removal of the freezer compartment that then allows the expanded refrigerator area to be used as a cooling compartment.  Power consumption is also reduced by removing the freezer.

The ‘three way’ refrigerator must be in a reasonably level position to operate as the gas ‘absorption’ cooling components and process is dependant on the refrigerator being level in both directions.

Remember to have regular maintenance carried out on your LPG refrigerator as parts can be subject to wear through vibration and age.

Dometic gas refrigerators have an automatic flame failure device that shuts off gas flow if the flame is extinguished and they have a gas indicator showing when gas is lit.  This is a safety feature to prevent carbon monoxide poisoning.

Carbon monoxide (CO) is an odourless, tasteless, invisible gas produced when LPG gas and other fuels like oil, kerosene and wood are burnt.  Do not block the ventilation panel located in the bottom of the door to your RV as this lets any gas escape.  As a safety precaution, in case a gas appliance ceases to work properly or the cowl is faulty, install a carbon monoxide detector or CO alarm.  Information researched indicates a CO alarm needs to be replaced when the sensor wears out and this may only take a couple of years although manufacturers of the SafeTAlert carbon monoxide detector and alarm state their product is a long life, self cleaning, maintenance free detector.

Compressor Refrigerators

Another type of refrigerator used in RV’s is the 12V/ 240V compressor refrigerator/freezer.  Two popular brands of this type are VitroFrigo and Waeco / CoolMatic Danfoss Kompressor fridges.  The capacity of these refrigerator/freezers range from 40 litres up to 230 litres.  There are models featuring two doors ie: one for the large freezer compartment and the other for the refrigerator.

For example the Waeco RPD 190 upright compressor is a 140 litre refrigerator and a 45 litre freezer which operates on 12V or 24V DC.  It runs off a Danfoss BD-50F Kompressor with a temperature range up to 50 degrees below ambient . It has an internal light, adjustable shelves, vegetable compartments and the doors (with patented door locks) can be adapted for left hand or right hand opening.  Depth 610mm x width 590mm x height 1340 mm (including flush mount frame) and it weighs approx 45kg.

Vitrifrigo compressor refrigerators are Italian designed 12V/24V caravan and motorhome refrigerator with an option for automatic cutover to 240V when connecting to mains power via a mobitronic.  However, the trend these days is to have the compressor refrigerator wired direct to the 12V battery bank and the batteries are charged whilst on 240V mains power or from solar panels.

The Vitrifrigo DP 2600 is a 240 litre fridge/freezer (180  litre refrigerator and 60 litre freezer) with flush mounted surrounds that runs off a Danfoss BD50F compressor.  It has an internal light, adjustable shelves, vegetable compartments and the doors can be adapted for left hand or right hand opening.  This Vitrifrigo refrigerator weighs 64.5kg and most of this weight is attributed to the insulated wall thickness of 50mm, the freezer insulation of 70mm and freezer door thickness of 90mm.  The dimensions are 590W x 580D x H1335.  Average power consumption – 40W/H.

Defrosting should be done whenever the frost layer exceeds a thickness of about 3mm as cooling efficiency can decrease and power consumption increase.  To completely defrost the refrigerator turn the thermostat knob to ‘stop’.  Don’t use anything sharp as this could pierce the refrigerator plate and cause irreparable damage. After defrosting, empty the drip tray and turn the thermostat knob to the desired setting. One tip with the Vitrifrigo refrigerators is not to push the drip tray too far back as it can interfere with the flow of cool air. We find our Vitrifrigo runs best when the thermostat knob is on about 4.2. 

On 12V power the compressor refrigerators have less draw current than the absorption refrigerators and if your RV is connected up to solar panels it will simply be charging off the power stored in your batteries and being charged by the solar panel array as you are travelling. Although manufacturers recommend these compressor refrigerators are best operated on a level surface it is not completely necessary as they have a tolerance up to about 30 degrees.

Types and sizes of refrigerators are similar for motor homes with the larger coach type motor home such as the Swagman having a standard two door 230 litre 12V with separate freezer. 

We have not gone into the intricacies of how these absorption and compressor refrigerators actually work mechanically.  If you want to know more about how an absorption refrigerator or a compressor refrigerator work do a search on line as there are a number of websites with information and diagrams.

Deep cycle batteries will be required to store the power to run these 12V compressor refrigerators when not connected to a 240V power source.  Most RV’s with compressor refrigerators will also have solar panel plus a solar regulator to supply power to the batteries. 

There are three types of batteries that are most popularly used in solar electric systems For more information on batteries see article - Vehicle Dual Battery System

Can I run my 3-way caravan fridge on gas while travelling ?

Definitely NOT.  This is highly dangerous.  All gas appliances must be turned off whilst your RV is under tow. Imagine what would happen if you cut an active gas line. There are just too many sources of ignition around, like a stone hitting a metal part and generating a spark.

Whilst in transit your ‘three way’ refrigerator is connected to an in-house battery or power is supplied by the tow vehicle battery/alternator.  If you stop for any length of time remember to disconnect the vehicle from the RV as it will likely flatten the vehicle battery.

The article from which the following extract on the climate class rating of refrigerators is reproduced by express permission, Collyn Rivers, Caravan & Motorhome Books, Broome, WA 6725.  This article is protected by Copyright.  www.caravanandmotorhomebooks.com

Climate Class Ratings

I to explain here just what I mean. A number of fridges sold in Australia are marketed as 'tropicalised'. Whilst this is a reasonable description of their design and construction, the term 'tropicalised' can unintentionally mislead those not familiar with fridge technology.

The increasingly accepted European Union (CEN) fridge performance standard, includes so-called 'Climate Classes' in which the most stringent is Climate Class T. And that 'T' stands for Tropical. So in the way that 'oils ain't necessarily oils', a 'tropicalised' fridge ain't necessarily Climate Class T.

There are four (CEN Standard) Climate Class ratings.

Fridges rated 'SN', and 'N' (which stands for Sub Normal, and Normal respectively) are designed and rated to work up to 32 degrees C.

Fridges marked 'ST', (which stands for Sub Tropical) are designed and rated to work up to 36 degrees C. Those marked 'T' (which stands for Tropical) are designed and rated to work up to 43 degrees C.

A correctly installed fridge Climate Class rated fridge can be relied upon to work satisfactorily up to the highest ambient temperature for which it is rated. But once past that temperature, cooling performance is likely to drop off. If, for example, you have a Climate Class SN or N fridge (ie. designed for 32 degrees maximum), but it's 42 degrees outside, the beer in that fridge is likely to be up to ten degrees C warmer.

So if you are planning to spend time in places that are very hot, it is prudent to use a 'T-rated' unit. I have yet to encounter anyone even locally using a correctly installed 'T-rated' fridge that was not completely satisfied with its performance. And I live in the Kimberley which is one of the most consistently hot areas of this country.

Do note that the European Union Standard that includes Climate Class ratings is not obligatory in Australia. Nevertheless Dometic and a few other fridge vendors market fridges in Australia that have the 'Climate Class' rating noted on their compliance plate (which you'll find inside the fridge). Climate Class T fridges were for example fitted in several display Winnebagos on display at the Casino Rally and many CMCA members have recently bought them.

Be clear regarding this: a statement that a fridge is 'tropicalised' does not imply that it meets Climate Class 'T' requirements.

Dometic states that its fridges that do meet the 'T' standard (and are designated accordingly on the compliance plate) are the larger models RM 2453, RM 2553, and RM 4601. The company claims only that its smaller fridges are 'tropicalised'.