Fridge on 12V killing the batteries
Just came back from the shop where I got my new batteries after I toasted my first set. I got them replaced 5 months ago, and already they were performing poorly, even thought they were supposed to be...
Forum Discussion
I was driving at highway speeds.
My charging system tops out at over 70 amps sent to the house bank. There is nothing wrong with the "system". It is simply a case of the ECM computer not "reading" the house bank. It reads the starter battery and behaves accordingly.
My fridge draws more amps (34) in 12 volt mode than it does in 120 volt mode (31).
Discharge of lead acid batteries is not linear. Assuming you can do 16 amps for 3 hours on a 100 amp-hour jar is quite speculative. Try it and post your results.
My charging system tops out at over 70 amps sent to the house bank. There is nothing wrong with the "system". It is simply a case of the ECM computer not "reading" the house bank. It reads the starter battery and behaves accordingly.
My fridge draws more amps (34) in 12 volt mode than it does in 120 volt mode (31).
Discharge of lead acid batteries is not linear. Assuming you can do 16 amps for 3 hours on a 100 amp-hour jar is quite speculative. Try it and post your results.
Kayteg1 wrote:pianotuna wrote:
Clearly even with twin #8 wires from the engine chassis system to the "house" batteries, there is a slow but steady loss. The alternator is a 130 amp Ford. The problem is the ECM just doesn't "see" the house battery well enough.
The solution appears to be to add an external diode to the alternator and charge the house bank from that.
I think something is wrong with your charging system or maybe you did idle the alternator- not letting it to put high amp.
My camper has 30 amp charging system that has #12 wire in the truck and might be even thinner in the camper.
I never put ammeter on that part yet, but I have electric jacks on camper that will not operate with 40 amp converter, but will operate with 30 amp truck charge.
So my 16 amp refrigerator draw is peanuts.
I see lot of members here whining without doing any math.
It is very simple - since I have 100 amp-hr batteries - the 16 amp draw should give me safe 3 hr of operation, or maybe 6 hr if I want to stretch it, still without killing the batteries.
No problem at all once the engine is started.
