I normally turn the fridge on 240 a couple of days before heading off, that way it is nice and cool. 12V will only maintain the temperature (depending on the ambient temp)not cool down. When we stop for longer than an hour or so I turn the gas on .

to Brickies and kenny,thanks for your info.cheers Ibbo.

ibbo wrote:

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I would like the assistance of fellow Grey Nomads about the right way to operate our three way fridge prior to travelling.Do Irun it on 240 to cool down,12 volt while on the road,then either 240 or gas when camped.I realise that this a commonsense thing but I have had a few suggestion that did not ring true.Obviously if we have a powered site we will use 240.Arent you folks glad I dont work on Aircraft anymore.lolCheers Ibbo.

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You are right, but an isolation switch on vehicle is good, so when you switch off motor, fridge is  not draining car battery.  Easy to forget to turn fridge off on short stops.   cheers

G'day ibbo  ...

I run my fridge on 240V for at least 3 days B4 heading off.  In that time I check that it works on both gas & 240v.

I stock the fridge with pre cooled/frozen stuff at least overnight before leaving.

Any spare space in both the fridge & freezer sections is filled with small plastic bottles of frozen water.  On long trips I re-freeze them in the camp kitchen fridge at Caravan Parks (good sources of cold water on hot days too).  A friend says that he uses rolls of bubble wrap to take up unused space.  The idea here is that when you open the fridge the cold air doesn't tumble out, which reduces the recovery time of the relatively inefficient absorption type fridges commonly used.


240v when possible.
12v when travelling - via accessory switch/relay or motion switch.
Gas when stationary - even for morning tea.

(I have been known to use gas when traveling in the far north .. risky & illegal)

Of course all of the important stuff is in the engel!

I have installed an indoor outdoor thermometer with a sender in the fridge that gives me an invaluable indicator of the fridge temperature.

Hope that this is of interest.

Thank you for your reply.I will follow your suggestions.They are very helpful.Cheers Ibbo.

G'day all ..

I agree with all of the preceeding comments about use of gas, filling empty space, Tropical rated absorption fridges, food temperature, etc. 

Given the poor performance of my T rated fridge on a touring trip thru the top end, I researched the subject of van fridges extensively.  On that trip I was travelling almost every second day (too much on the road some would rightly say - our new traveling 'rules' has fixed that).

I found that a major contributor was the poor installation in many vans .. eg -

- Not insulated round the sides/top of the fridges. This allows pockets of hot air to form

-Top air vent too low (should be above the top of the fridge)

- No guide to assist a smooth air flow to exit via the top vent

- Air gap between the fridge & van wall too wide.  The air flowed along the van wall & not over the fridge coils etc. This is a key issue.  A couple of baffles coming within 10mm of the top & bottom of the rear of the fridge fixes this.

- Computer fans placed at the bottom blowing air.  Work best if placed at the top gently sucking air through.

Of course the way you position the van on site has a major effect with afternoon sun on the fridge side effecting performance.  Use of shade cloth assists.

The size of wire from the vehicle to the fridge & poor connectors is a common problem for 12v operation

We could go on & on about Van fridges.  There are some good reference web sites about, with most offering sound info.

Hi brickies ..

I think this is how it works ...

The Andersen plug lead is usually used charge the van battery when driving.

The fridge when driving & switched to DC is powered via terminal 2 of the round or flat trailer socket/plug.  It is this wire size that is critical  .. I think that it should usually be ISO 6 gauge.

(I think that I should have a close look at the issue of the output of the charging van battery to see if it is in parallel with the terminal 2 lead - I think not  .. maybe others more expert than I might like to comment)

-- Edited by Cupie at 10:45, 2008-12-01

Cupie wrote:

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(I think that I should have a close look at the issue of the output of the charging van battery to see if it is in parallel with the terminal 2 lead - I think not  .. maybe others more expert than I might like to comment)

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This worried me so I got out my trusty meter & checked ....

With the fridge on DC & no connection to the vehicle there is no 12V at the fridge DC element.  So as I suspected the van battery is not switched to the fridge (at least on my 99 Jayco).

However, if U look at the circuit, -

. When the fridge is switched to DC, and

. with both the trailer plug & Anderson plug connected and

. with the vehicle ignition on (or switched to 'Accesories') 

Then the both batteries are in parallel.  This is largely academic with respect to the fridge as its operating current is supplied only via terminal 2 of the trailer plug.  So that wire size is critical for efficient fridge operation.

Wire Size ..

My fridge documents confirm that the wiring from the vehicle battery via terminal 2, minimum size is -

. 4(square)mm for up to 5m length &

. 6(square)mm to 8m

(this is cross sectional area of wire)

Basil Faulty wrote:

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You will find that there is an isolating diode in the van somewhere to stop the van battery trying to provide current to start the vehicle. Usually there is a system of voltage regulation to make sure the van battery is not overcharged by unlimited current. So while it is strictly speaking being charged in parrallel it is not connected in parrallel...

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Thanks  Basil ... what U say sounds logical ... so I went & had a look and there is a whopping great diode & heat sink in what looks like the battery leg from the anderson plug.  I have a mysterious Mexican made Centurion 'Switching Power Converter' which of course comes with no real information.  I suspect that it also has some sort of smart charge functionality.  At home, it keeps my van battery on float charge 24/7.

In my case it is all rather academic as I don't use the anderson plug facility.  I almost never bush camp & the van battery is charged at the van park .. if I happen to use it to operate the waterpump when stopped for lunch etc.  If I become a bush camper than I'll probably wire in the anderson plug to charge a replacement van battery when traveling. 
I'm about to use the van battery (in its first real use) on a trial of an electric motor on my latest toy, a Viking Tempo Fisherman kayak  .. given that the battery is around 9 years old, I don't expect too much from it but it went OK in a wheely bin of water.

ps. Wouldn't it be nice if the van came with a wiring diagram.

I have an old Electrolux three way fridge in our van.  Could do with a new seal on the door.  Almost had a cry when told that I could not buy a new seal, I had to purchase the entire door skin which has the seal built in.  All to a cost of $350 ex Brisbane and $380 ex Cairns. 

On second examination the old seal is working just fine and dandy.

Ian and Pauline