Battery charging

[Rick i Carter]

On my 2004 NationAl Tropical I have noticed when I am plugged into shore power for more than 4 days my starting batteries are low I have tried the battery boost an it did not help I had to use jumper cables from coach batteries to starting batteries to start the motorhome .when plugged into shore power does it also charge your starting batteries ? or just charges your coach batteries.I know I need to have my starting batteries checked an replaced if required .thanks Rick 

[Kirk W]

16 minutes ago, Rick i Carter said:

when plugged into shore power does it also charge your starting batteries ?

While I'm not sure about a National RV product, I do know that many RVs do not. It has become more common place to do that now than it used to be. With the Cruise Master we lived in, that was not the case so I got a Battery Minder and mounted it next to the starting battery and kept it connected all of the time and then connected the 120Vside to an outlet that was tied to the coach system. That way anytime that we were connected to shore power the chassis battery was on float. I found that it greatly extended the life span of that battery. 

You should be able to trace the circuit from your converter to the chassis battery if you have that feature. Another way to tell would be to monitor the voltage across the battery with the engine off and first no shore power and then with shore power. You should see some small increase in the voltage as soon as shore power is connected if you have charging from the converter. 

Edited September 27, 2020 by Kirk W
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[Rick i Carter]

Thanks Kirk I will check that out