So you’re looking for a motorhome fridge that can run from your car battery as well as via a normal electricity connection? You might even be after a model that can run off LPG gas, or maybe you just want to keep drinks cool while you’re travelling.

There are three types of portable fridges to choose from with big differences between them: 

•    Thermoelectric
•    Compressor
•    Absorption (3 way)

You need to know what you’ll use the fridge for to choose the right type.

What to look for:

• Type: If you want to be able to run the fridge on gas, you’ll need an absorption model. If you only need to run it  off your vehicle battery or electricity, a compressor or maybe a thermoelectric model is more suitable. 
• Compartments: Think about what you’re likely to put in the fridge, and whether you need a fridge or freezer or a model that can be both at the same time. With the portable models, removable baskets may be easier to use than one deep compartment that you have to reach into and search for things. 
• Battery drain: If you’re likely to run the fridge often when your battery isn’t being charged, consider how much current it’ll draw. If you are using your vehicle starting battery to run the fridge, consider a model with in-built battery protection. These can cut out at a certain voltage to prevent the battery going flat. Alternatively, run the fridge off a second battery.   
• Control & Display panels: Check how easy they are to initially set and adjust as conditions change in order to maintain the right temperature. 

Compressor models (12V/24V)

These operate in the same way as your fridge at home. They run on a 12V or 24V battery or from 240V mains electricity (usually by using an adaptor). On the whole, compressor models work better than the thermoelectric or absorption ones. Compressor types can pull the temperature down quickly and to around 50 degC below ambient. They stay cold under a wide range of ambient temperatures.

The Waeco CF range has an easy to use temperature control. Just set required temperature and then view the actual temperature on the display.

Compressor fridges and bring the temperature down quickly and the internal temperature fluctuations are minimal. We have logged the air temperature fluctuation inside a Waeco CF50 fridge and it there is only a 1.5 deg change from the set-point temperature.

Scenario
The Nelson family are looking for a caming fridge. They like to hit the road as often as they can. They mostly stay in caravan parks or camping grounds with powered sites, but not always, so they’ve set their car up with a dual battery system and wired a compressor fridge into the second battery, which provides power to the fridge without causing car-starting hassles. George is also a keen fisherman and uses the fridge to store his bait — and hopefully the big haul from his fishing trips.

Absorption models (3 way)

If you’re keen to connect to gas, an absorption model is your only option. They are refere to as "3 way fridges" because they can run on 3 modes; 230V, 12V and Gas. This style of fridge has been around for many years; it doesn’t have a motor but relies on the cooling effect of a liquid (in this case ammonia) when it evaporates into a gas. For this it needs to be level, have a well ventilated condenser plate and to have a heat source. The heat source can be from a heating element powered by 12V or 230V or from a gas flame. Being able to use gas as the power source makes it handy for free camping for prolonged periods in more remote locations.




Scenario
The Hintons are serious caravaners, who like nothing better than to spend time in remote locations. They find the best 'caravan fridge' for them is a 3 way model. First they get everything cold at home on 240V, then run the fridge/freezer from the vehicle battery while driving to their destination, and finally set their fridge too LPG mode once they arrive. If they’re travelling on rough and hilly roads it doesn’t work very well, but it’s better than nothing, and it works well once they’ve stopped and have set it up level.

Thermoelectric Models

A thermoelectric system produces heat or cold at a junction of dissimilar metal conductors where a current is flowing. They’re really designed as short-term coolers or warmers. Although they have a limited cooling ability, they’re still a substantial drain on the car battery (almost 5 amps) – You’ll need to disconnect them when you turn off your engine. They can cool up to 30 deg below ambient temperature, noisier than other types of fridges but are the cheapest of all the models we have talked about.