How do you leave the batteries?

[Tony Tommasello]

On the hard for the winter - disconnect the ground. No electron flow. Marginal discharge until spring commissioning.

[thinwater]

Originally Posted by a64pilot

OK short time as in like gone for a week or two, shore power connected and batteries on float.
Long term as in gone a couple of months, disconnected, assuming boat on the hard, but if in the water and the batteries are disconnected, whats going to power the bilge pump?
Now if I lived up North and boat on the hard for Winter, batteries are coming home with me and kept from freezing and probably on float.


Sent from my iPad Pro using Cruisers Sailing Forum

Charged batteries don't freeze, and they self-dischage very slowly in the cold. Depends on how long.

Also, most folks have some solar, which functions just fine on the hard (depending on the snow!).

If I will be gone more than a few weeks, solar on, shore power unplugged.

Just sayin'.

[thomm225]

My boat is in the water, and not hooked to shore power.

I let the solar panel charge the batteries (two 12 Volt batteries in parallel)
until the meter pegs above full then disconnect for a few days to a couple weeks. I usually plug the panel (100 Watt) back in through the $12.00 controller when the meter shows about half.

If I plan to sail on Friday or Saturday, I try and plug the panel back in a day ahead of time.

[Sailingketch]

We are only on the boat on the weekends and while gone I leave the battery charger on, the refrigerator on, and the bilge pump active. I have had no problems but I would like to know if there is any danger here leaving the refrigerator on (12 VDC).

[Sailmonkey]

Originally Posted by Sailingketch

We are only on the boat on the weekends and while gone I leave the battery charger on, the refrigerator on, and the bilge pump active. I have had no problems but I would like to know if there is any danger here leaving the refrigerator on (12 VDC).

Yes, if you arrive and the beer is cold you're in danger of drinking it.

[Kenomac]

If the boat is stored out of the water, turn everything off, clear out all the fresh and salt water lines, leave the freshwater tank empty, shut off power from the batteries to the engine and genset so there's absolutely nothing connected to the battery bank, then leave it unplugged from shorepower. The batteries if good, will still be at better than 50% when you return and you won't have any risk of you boat catching fire due to an electrical problem.

Boats sometimes burn up when left plugged in and unattended. If your boat is to remain in the water, that's a different story, you want the bilge pump to always have power.

[a64pilot]

Originally Posted by Sailmonkey

Yes, if you arrive and the beer is cold you're in danger of drinking it.

Yeah, I only turn mine off to defrost, we are usually there on weekends, and it takes a day to freeze both cold plates and get the freezer down to temp, then one day later you leave and turn it off? So I leave it on, plugged into shorepower and right now with the AC on dehumidify.
Be different if I weren't in a Marina.
I don't live up North and don't decommission my boat for winter, winter just sometimes means no diving, but good sailing and flipping the AC's from cool to heat for a month or so.
Right now is the time of year when the winds die, and the Africa Hot sets in

[hellosailor]

Tony-
The manual is correct. Disconnecting the batteries when unattended will ensure there cannot be an electrical fire from the batteries or charger. Haul your boat for winter yard storage in the NYC area and the fire marshal may actually be handing out summonses for any boat that is plugged in to the AC while unattended. Your mileage may vary.(G)

Of course the ignores the fact that when left unattended for even 30 days, irreversible sulphation occurs in the batteries and they permanently lose power. The maker knows this, but new batteries are cheaper than yard fires.

So if you have a good charger. And your yard/marina allows it. And you are Real Sure that leaving your batteries on solar or trickle charging won't dry them out and start a fire, by all means keep them topped up. Just be aware of what the price could be IF there is a problem.

Your choice. (Unless the yard staff wander around and disconnect unoccupied boats from the AC.)

[sailorboy1]

What's shore power?

[deblen]

Originally Posted by Tony Tommasello

On the hard for the winter - disconnect the ground. No electron flow. Marginal discharge until spring commissioning.

I'm in a hard freeze area for 5 mos. & that is what I have done for yrs.
Make sure they are fully charged & disconnect the grounds.
I also have a 1" bronze garboard drain.

Caution: if bilge freezes & thaws,the bilge pump can freeze.

[Adelie]

Originally Posted by leftbrainstuff

Batteries like to be charged. Why does the oem recommend not leaving the charger on? Not what i would consider best practice.

A small solar panel or regulated solar is a good compromise. No shore power issues to worry about.

Sent from my SM-N900T using Cruisers Sailing Forum mobile app

As a guess because they don't want to get into the intricacies of explaining to a non-technical owner what an appropriate unattended charging system would be. Easier and more legal defensible to just say "Don't".

[foufou]

I leave charger on, float state, and backup is solar low wattage trickle chargers. Batteries are AGM over ten years old and still strong. Nothing wrong with this.

[jamhass]

What Nigel said ...

Shore power is often the major source of galvanic action, eroded zincs, etc etc. Only takes a small bit of solar with a proper charge controller to keep all quite happy.

We've been leaving our boat (with AGM's and solar) for 4-5 months at a time in Mexico. Batteries have been just fine, got 8 years out of the last set, so gotta think we've got the unoccupied battery plan down OK.

[Uncle Bob]

Originally Posted by jamhass

What Nigel said ...

Shore power is often the major source of galvanic action, eroded zincs, etc etc. Only takes a small bit of solar with a proper charge controller to keep all quite happy.

We've been leaving our boat (with AGM's and solar) for 4-5 months at a time in Mexico. Batteries have been just fine, got 8 years out of the last set, so gotta think we've got the unoccupied battery plan down OK.

+1 My batteries are FLA, fridge runs 24/7 except for defrost and here in Sydney I have never seen my batteries fall below 12.8 volts. Been like this for a couple of years now. Oh how I love a good solar system !!

[savoir]

Now mine spend winter in the garage on a couple of sheets of cardboard box. The winter before last was pretty mean in RI and all 8 of my batteries died because I left them on the boat.