# 12v fridge - switches off with low (but not dead) batt



## numberwrong (Jul 14, 2010)

I have a 12v Camping Gaz fridge which has a cleaver but annoying mechanism in it which turns the fridge off when the battery gets low.

It seems to turn off at around 12v as it's designed to be run off a lighter socket using your main starting battery but I have a deep cycle lesure battery.

Basically I want to stop it doing this. Ive had a look inside the the fridge but its a PCB with a chip so its a bit beyond me to disable the voltmeter. 

Is there something that keeps the output of a battery at a constant 13v to trick the fridge in to thinking the battery is OK?


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## peribro (Sep 6, 2009)

Since repeated discharging of your battery to below 12v is damaging to it and will shorten its life, I would have thought that your best solution is to find a way (if possible) of keeping the battery charged to above 12v. That way you will get the best of both worlds - a fridge that is on and a longer lasting battery.


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## numberwrong (Jul 14, 2010)

I'm running the fridge off a deep cycle lesure battery on a split charge system which isolates the lesure batt from the main when the engin is not turning over. 

(I may be wrong) But unlike a normal car batt I thought is was ok to run the lesure batt down?


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## trevorf (May 16, 2005)

Not a good idea to run down your leisure battery to below 50% charge. Doing so will shorten its life. Your fridge is doing you a favor by shutting down before causing damage to your battery.
I agree with peribro. You need more batteries and/or a method of charging them. (Solar panel/gennie etc)
The other alternative is to replace the fridge with one that runs on gas.


Trevor


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## numberwrong (Jul 14, 2010)

Ah yes, I so pose the fridge is quite power hungry (54w) but my 80ah battery should keep it running for about 5hrs, at the moment it lasts about 1 1/2 hrs - it was quite a cheep battery tho..


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## peribro (Sep 6, 2009)

You should certainly be getting more than 90 minutes - more like 8 hours I would have thought if you have absolutely nothing else drawing power from your leisure battery. I think you need to check that your battery is properly charging and that nothing else is draining it. There have been previous posts on how to do this and I'm sure someone else far more knowledgeable than me on the topic of batteries will post on here.


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## numberwrong (Jul 14, 2010)

After a long drive my leisure battery is around 13v (tested using a meter). Is this high enough? 

I have an LDV convoy petrol, I asume the alternator has the power to fully charge both batteries..?


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## MikeyB (Jun 20, 2005)

You state that your battery is "around 12V". This is actually well on the way to being almost discharged.
100% charge is 12.7+ V
75% charge is 12.35V
50% charge is 12.05V
45% charge is 12V

all figures are approximate of course, and in colder weather are even less, but you can see that at 12V the battery is more than half discharged. Whilst it will still function for a while, running it at this level could risk you not being able to re-charge it very easily. Many devices will power-off at 12V, despite them being actually rated as such, simply to avoid damage to either itself or the battery. Mike.


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## numberwrong (Jul 14, 2010)

oooh every day is a school day!

thanks for the advice.. I think more research is in order before more questions!!


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## peribro (Sep 6, 2009)

Is your battery holding its charge? With it fully charged (12.7v+) and nothing connected / drawing current from it, is it still showing 12.7v+ after 24 hours? If so and if the only thing that you then operate is the fridge, then it must be that it is drawing more current than you believe it is. Perhaps it is faulty?


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