Hi all; Check to see if you have 12 volt at the end of the 12 lead that plugs into your engle fridge. If not back check your cabling. Have a close look at were the 12 Volt and the 240 volt plug in to the back of your fridge. There could be a blade fuse ( 15 Amp ?? ) just near the sockets. This have blown. Worth a check to see if it has, I think that fuse is only for the 12 side of the fridge.
You could make a testing cable & connect the fridge straight to the battery & check voltage at the same time. If the fridge works then it is something between the battery & fridge.
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50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
A 14 year old fridge will have R22 refrigerant, these days they are using R134a which doesn't work as well so you will have to help the fridge in other ways like as cool as possible ventilation.
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Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
In this thread I did extensive tests on my fridge at 35°C ambient temperature I could only get the fridge down to -10 reliably, sometimes getting to -12.
It would get to -23 without problems but the ambient temperature can't be any more than 45°C more than -23.
Another thermometer was showing the fridge would get to -25 but realistically it's about -23.
I've tried pushing more air through the condenser but the difference of 45 is about it. The only other option is to water cool the condenser but that all becomes very messy.
Hi Gypsy2600; You do not say what size battery you have ( Ah ), having a battery to small and your fridge would soon bring the battery down to 50% state of charge and the fridge may be shutting down as it has sensed the battery be to low. Even having a battery of 100 Ah you only have around 50 Ah to play with and these fridges draw around 4~5 Amps, so you are looking at around 10 hours of use. How is the battery charged and at what current and last what size cable has been used from the main battery to the auxiliary battery and on to the engle fridge. Battery voltage loss could be your problem.
I did a 6 hour test with my 28L fridge set at its lowest setting of -22. The lowest the fridge displayed was -13. The 3 seperate thermometers showed -12.8, -13.0 & -12.1. Room temperature ranged from 34.5 to 35.0.
Over the 6 hours the fridge used 0.258kWh & this is with an additional 60mm of foam covering the fridge.
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Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
Does the car have a smart alternator as most cars do. The battery probably will never be fully charged. One of the reasons I have installed a DC-DC charger.
Have you isolated the auxiliary battery & fully charged it overnight with a 240 volt smart charger. Then run the fridge off the battery for a couple of hours. If the fridge works well then it will be clear the fridge is not the problem.
__________________
Procrastination, mankind's greatest labour saving device!
50L custom fuel rack 6x20W 100/20mppt 4x26Ah gel 28L super insulated fridge TPMS 3 ARB compressors heatsink fan cooled 4L tank aftercooler Air/water OCD cleaning 4 stage car acoustic insulation.
If you have the auxiliary battery in the engine bay fully exposed to the heat this is not a good idea. My starter battery is in the engine bay but fully enclosed from the engine bay & gets a lot of seperate ventilation. On top of this I have installed heat shielding around the battery. The auxiliary batteries are inside the car, 2 under a seat.
Although not ideal you could put a second battery in the boot & charge & draw from a mid point within reason with 4awg cable & fused both ends. The warmer battery should be charged at a slightly lower rate but you probably just be better living with a slightly shorter life of both batteries.
Do you need to run the fridge as a freezer at -15 as this uses 5 times the amount of energy.
-- Edited by Whenarewethere on Wednesday 6th of November 2019 07:52:07 PM
A torture test to see how long it takes to freeze 10.5 kg of ice bricks to -22C, lowest fridge setting. On previous tests thermometers I stuck in the fridge showed -24. Fridge cover & 2 thicknesses of 10mm foam. Aluminium heatsink to "butter" compartment.
Ambient temperature over the days was 26°C morning & night, including ice bricks at the start. Fridge sitting on carpet.
I also put a thermometer in the centre of the ice bricks as this area is slower to freeze.
24 Hours: fridge -11, centre of ice -2
36 hours: fridge -16, centre of ice -10
44 hours: fridge -20, centre of ice -16
46 hours: fridge -22, centre of ice -19
The fridge started cycling at 46 hours.
About half the time it was running off a car hattery which was around 12.4 volts with a trickle charger. Fridge current was 3.1 amps.
I could hear the compressor running a touch faster on AC but not a lot in it.