House battery charging by alternator
I am trying to understand how the charging system works on our 2007 Coachmen Concord. It seems that the truck alternator charges the house batteries at different times. For instance on a recent day t...
Forum Discussion
CA Traveler wrote:
X2 I'm not aware of any MH that doesn't charge both banks from the alternator. Most likely problem is the solenoid as significant amps are involved ...
This has been discussed MANY times. It is NOT just about amps, volts are an issue.
For about 20 years, auto manufacturers have been installing "smart charging" systems on vehicles, even motorhomes. These systems limit the voltage out of the alternator a few minutes after the engine starts, down to about 13.2V ! You will never fully charge a depleted house battery at that voltage.
Prove this to yourself. First, run your house battery down at least 10%. Start our engine. Immediately check the voltage at the vehicle battery and at the house battery. Drive for about 10-15 minutes and with the engine running check both voltages again.
If you are not getting >14V at the house battery, you will never fully charge that battery.
