Charging and Using 12V at the same time

[BlueAce]

I have been leaving a small 12V ventilation fan runningwhile I am away from the boat.I leave the House battery connected,and the 12V charger (resonance type) running.Seems like the charger is overcharging the house battery,and causing the battery to lose water. I guess I need to remove all load from the battery/charger(i.e. dont run the fan) to prevent this?If I want to continue to run the fan, what do I do to prevent overchaging on the battery?

 

[larry w.]

fan it

Blue Ace; Try one of those solar vents first. The have a tiny solar panel that powers a small fan. You might want to dump that reso charger and get a smart 3-stage charger that has a "float" function, or disconnect the charger and put a moderate size solar panel aboard to keep the battery up.

 

[BlueAce]

does smart leg charge OK under load?

Yeah, I just bought a smart leg charger, to replace the reso. But, the charger directions still recommend "no load" charging. I was trying to avoid the solar fans: I dont like they way they look, and they dont move as much air, and I did not want to cut another hole in my cabin top... But, maybe that is what I should do...

 

[larry w.]

fanning

Blue; What's a "leg" charger? What about a 110v fan? Does your boat have a 110v side? Or a solar panel.

 

[Bill C320 Papillon]

110 v

While in the slip, I keep a small 110v fan running as well as a 110v trickle charger to keep the batteries topped off.