house batteries not charging while outboard is running

[genehelfman]

2024 r27. After 2 days on solar power only with fridge on, we ran for three hours at 1500 rpm (saving gas) and got the "low unit charge" warning and a reading of 11.1V. on the house batteries. We shut off fridge, autopilot and GPS/chartplotter and ran another hour and the house batteries only rose to 11.4 (Victron read 41%). Engine and thruster batteries were fully charged. Shouldn't the house batteries charge while engine is running. It does charge when on shore power but only to 12.8 v.

 

[SKing]

Lithium or AGM

If lithium than you have a DC to DC charger that is feed from the start batteries which charges the house Bank.

On AGM you have a ACR that ties the house and start batteries together to charge the house bank.

 

[Submariner]

2024 r27. After 2 days on solar power only with fridge on, we ran for three hours at 1500 rpm (saving gas) and got the "low unit charge" warning and a reading of 11.1V. on the house batteries. We shut off fridge, autopilot and GPS/chartplotter and ran another hour and the house batteries only rose to 11.4 (Victron read 41%). Engine and thruster batteries were fully charged. Shouldn't the house batteries charge while engine is running. It does charge when on shore power but only to 12.8 v.

Check your ACR in the port lazarette and make sure the yellow ground wire hasn't fallen off. If it has before, ensure that it's in the correct position. (There's 3 spots to plug it in, only the spot labeled "ground" is correct). Without the ground wire on the engine to house ACR, engine charging can not occur.