Just noticed my fridge was on even though the switch on the fridge was on 240v. I'd had it disconnected from the mains for probably 24 hrs and its obviously been running on the 12 volt battery. luckily i noticed otherwise it could have trashed my battery if it flattens them to much and left for any period.
I had no idea it would run on the battery when the fridge switch was on 240 volts!!

if your fridge was switch was on 240 volt then the fridge would be on and your batter would be topped up from your on board system, or am I miss understanding your problem.
if you disconnect the mains power lead and your fridge is still switch is set on 240volt and still operating the you do have a problem possibly with the fridge.

My manual says to select the energy source for the fridge: gas, 230Vac or 12Vdc: it does not say that the fridge will use the 12V supply if the switch is set to the 240Vac source when the latter is not present.

All it says it that the fridge will use the battery of the towing vehicle if it senses an alternator signal otherwise it will use the onboard caravan battery (when the power source of the fridge is of course set to 12V)

So if you set the fridge to 240Vac operation it would (should) only work when the van is on EHU.

On modern vans the conventional system is that the fridge internal light, controls and display run on 12V from the van battery, no matter which form of energy is being used to refrigerate.

The actual refrigeration is either 12V from the car's alternator or 240V from an EHU or gas.

So if the fridge is switched to 240V but disconnected, the interior light and display will still operate. Without that system there would be no light or display when running on gas. And if the fridge ran on 12V from the van battery it would flatten it in very short order.

Right well explains a lot, I had no idea it could segregate refrigeration from lighting etc. I must make sure when I disconnect the mains & I’m not using the fridge/caravan to make sure I switch it of properly to stop it trashing my battery

If you switch the fridge off when you empty it the display will stop and the interior light won't work and it therefore won't drain the battery. I believe that vans with the modern display type fridge also have a 12V on/off switch for the whole system.
Earlier fridges without light or display didn't have a 12V feed from the van battery and therefore didn't have a 12V on/off switch.
It's a very common misconception that the fridge will run on 12V from the van battery. As said, it relies on such power but the actual refrigeration only runs on 12V from the car's alternator when connected to the car with the engine running at over 1000rpm.

Arcane knowledge only for the initiated
Dave

Quote: Aaron Calder wrote in post #7

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'Internal light', 'controls' and 'display' on an Eriba fridge?

What is this magic of which you speak?

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