Battery Charging Problem ***UPDATE***
While dry camping in freezing weather, the charging system died for the dual type 24 house batteries (2002 Winnebago Mini). It appears to be a solenoid system. It failed two years ago and the RV s...
Forum Discussion
LOG wrote:
Sorry. I did not ask the question adequately.
In a motorhome after 2018, with a smart charging system, the alternator will never fully charge the house bank unless it has a DC to DC battery charger.
If that is correct, please explain why. Thanks.
It is correct.
IF you had 168 hours, with no loads, and constant charging at 12.8 volts--then the house bank would become fully charged.
At 13.8 volts the ECM "sees" the starter battery as full. Mine drops down to 13.2. But we don't drive constantly for a week at a time.
Trojan suggests 14.8 volts be used. That only happens in the vehicle if the starter battery is quite discharged, and not for very long at all.
Then you have voltage drop to contend with.
When my RV is in storage the solar charging system does get the job done--but it takes a week or so to get to 0.0 amps of charging. My bank is 566 amp-hours so at 25 C (77 f) fully charged is about 2.9 amps going into the bank.
I do use a trik-l-start to maintain the starter battery. My first batteries lasted from 2009 until 2017, and the starter battery a similar length of time. I moved to AGM telcom jars because laying down in the snow to check battery electrolyte levels is not much fun at -35 C.
