Easy way to upgrade to AGM?

[antanasr]

Hello cruisers!

I've got a 1984 Seidelmann 295 that's been sitting for a few of years and I'm sprucing her up to sail once again. It's time for electrical

The previous owner, who is unfortunately no longer with us, had two basic Diehard batteries - one Gold and one Silver. There's a standard battery switch. It charges from the alternator and shore power (on that it only charges when both batteries are set to off. I plug in, turn off the batteries, they charge and the AC outlets work but not the panel stuff. So I can't have access to house power when charging at the slip).

I would like to upgrade to AGM, as I am adding 200 Watts of solar and wish to have enough power to run a laptop and an audio interface I compose and record music with. It's good for creativity, this anchoring lifestyle.

Now, solar was super simple to figure out. Got the panels, an MPPT controller, a battery monitor. All seems to be plug and play with whatever battery (Renogy's Rover controller claims it will auto detect and do what it needs to).

Figuring out the alternator/shore power situation has been more challenging. I've got a Yanmar 2gm20 with it's stock alternator rated at 55 amps. There is a 15 amp AC to DC battery charger. I assume I need a new battery charger for shore power and something to help with the alternator output.

If we forget the solar, am I being naive in thinking there should basically be two bits of gear that I need to add?

Is there some sort of controller that can accept dual input from both, the alternator and the solar?

[smac999]

buy agm and stick in. they charge at 14.4-14.7 volts just like flooded

charger gets wired direcly to both batteries. alternator can stay where it is. probaboly goes to starter, and only charges the battery that is slecteced on swtich. this can be left up upgraded to easier system.

solar connect to house battery.

everything just connects to batteries and all or some will charge together. no need to overthink or try to control all

the batteries should definitely be charging from shore no matter where the switch is...

[MikeHoncho]

Figure out which AGM and go with its specs. My Lifeline, as most AGMs will take a ton of amps for a extended amount of time which overheats and burns up internal regulated alternators if the battery big enough. The specs will tell you the recommended min amps for charging with shore power for optimum battery life. Don’t just buy one and drop it in until your do your research and know your specific needs. I went from flooded to a Lifeline 8d with 240a/hrs (20hrs). I had to switch out my non-stock, internally regulated alt for a externally regulated alt and regulator with thermal sensing on my 2gm20f.