New Owner - Used 176

Double check to ensure that an adaptor is not installed on the shore power end of your shore power cord.  If that cord is heavy (10 gauge wire) "I think" that your trailer is wired for 30 amp service which you should definitely verify.  The adaptors that allow a 30 amp shore power cord to be plugged into a 20 amp home outlet can be very deceiving a "look" like they are part of the shore power cord when in fact the adaptor is removable.   Hope this helps 

Contrary to popular belief cold is good for batteries. They are filled with sulfuric acid and constantly chemically corroding from day one. Chemical reactions are accelerated dramatically at higher temps. So if you live in the UP of MI you will get much longer battery life than if you live in FL or AZ. The reason batteries tend to ultimately die in cold weather is because the chemical reactions which release energy from them are slowed down then as well. So batteries age in hot weather but tend to die in the cold. Bottom line is, don’t expect long battery life in a warmer climate. And the idea that placing batteries on concrete is bad is a myth.

If you really have a 25 amp connector on your cable then it’s only good for 25A, not 30. You don’t want to run 30A through it via an adapter, it can overheat. Get a proper 30A cable and connector.

Hi JR,

Originally posted by StephenH Battery testing just off a charger is not the most accurate. That is surface charge. The one where it sat for an hour or two before you tested is the more accurate test. https://www.autozone.com/diy/battery/how-to-test-a-car-battery-with-a-multimeter The 12.6V reading indicates a good battery. However, it still would not hurt to take it to an auto place and have them put a load tester on it. That will be much more accurate than just a multimeter.

+1 on allowing the battery to rest at open circuit (no charging or discharging) for awhile before measuring the voltage. Also, don’t worry about voltage differences of 0.1 or 0.2V, those are within normal battery variations. The test in the link is good for an auto starting battery which isn’t expected to deep cycle, but for a deep cycle battery like you would use in an Rpod you should pull some charge out of it and then check it. The easiest way is to first get the battery fully charged for a day or two with no load. Then let it rest for a half hour or more and measure the voltage. Then turn on the fridge on 12V for a known period of time. The fridge uses about 11-12 amps so if you run it for 4 hours that’s 44-48 amp hours, so about 45% state of charge on a typical 100 amp hour rated battery.

Turn off all loads and let the battery rest of another half hour to and hour. Measure the voltage again, it should be at or a bit over 12V. If not it’s probably getting to the point you want to replace it if you plan on boon docking much. Be sure to recharge the battery again right away, don’t leave it discharged for any length of time.