Fridge on 12v

[MikeP]

My caravan is wired very simply; 12v feed to battery, 12v feed to fridge and an earth for each. No relays, no fuss. I have used an old 12S socket and bridged pins 3+7 (earths) and 4+6 (4 from battery, 6 to fridge) with 17A cable. The effect of this is that I can run the fridge off the caravan battery during a short ferry crossing or when parked up for a meal. I have tested it whilst using the hookup at home, and the fridge got cold fairly quickly.

Here is my question. Does the fridge have two elements, one for 12v and one for 240v? If so, I suspect it would be better to cool the fridge before a trip by using the hookup, my funny 12S socket and 12v source. But if it has only one element then 240v would do the same job. Does anyone know? It is a basic Dometic.

I know I can't expect too much from a leisure battery compared to the charging output from the car, but I am hoping that every little helps.

 

[Guest]

Your fridge will have 2 separate elements, one for 12volt and one for 240 volt. The 240 volt one has a thermostat so it switches on and off while on site. The 12 volt is permanently on which is why towball wiring kits include a relay to isolate the fridge when the car engine is not running, or you would soon flatten your car battery. It is always recommended to use either gas or 240 volt supply to pre-cool the fridge before using the 12 volt system. If your fridge is cold then a crossing such as Dover-Calais is unlikely to make much difference. An overnight crossing, yes, but just how much really perishable food are you carrying. Milk etc will live happily in a cold car deck and you can buy new stock once you dock. It is only frozen food where you would need to be carefull.

 

[MikeP]

Thanks for the swift response - very helpful.

Dover/Calais - including the check-in time, the fridge will be off for 2

 

[Guest]

Don't know how big the freezer compartment is in your fridge but normally you can't get that much in there. For Dover-Dunkirque your fridge is not going to 'warm' up very much especially if you keep the door closed tight. It is insulated quite well.

Sorry, but part of the fun for us is 'hitting' the French supermarkets and getting stocked there. The wife in the food and me in the wine.