Veebyes wrote:
Think of that battery charge as a bucket of water. Once it is gone, it is gone. Time to refill/charge. The rated amp hours of the battery is the size of your bucket.
For dry camping the size of the battery bank & available water capacity is king.
A good analogy but may erroneously lead the OP who is a newbie to the conclusion that he has the rated AH of his battery available for use when in fact he shouldn't be drawing that battery reserve down any more than ~ 50% on a regular basis if he expects that battery to return it's rated number of deep cycles before permanently expiring. That means drawing down to about 12 volts, so if he's already at 12.2 he's already drawn down to ~ 60% capacity with very little left to go before a recharge would be recommended. In other words, if the OP has a battery with a 90 AH rating then in practical terms he would have only ~ 45 AH available for use before a recharge would be needed.
The OP's comment that "nothing" is running is untrue as
every trailer will have some parasitic draw whenever the battery is connected - propane detector, radio memory circuit, television wall plate if one forgets to turn it off, etc. If not plugged into shore power so the converter can maintain a correct charge on the battery that battery should
always be disconnected whenever not being used to prevent this parasitic drain. Reading the OP's posts suggests to me he hasn't done this, his battery has in fact been drawn down well below 50% SOC, and is in fact toast, the proof being his converter's apparent inability to properly recharge that battery.
