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altamont · 12-13-2008, 10:22 PM

I left a fan on in the bathroom to help dry out our carpeting. I thought that we had our land line hooked up, but it was not. I went into the trailer and the batteries were TOTALLY dead. I have heard that when you take the batteries (2 years old, wet cells) down to zero, they are ruined. Do I need to buy 2 new batteries for Christmas, or can they old ones be resurrected?

Airslide · 12-13-2008, 10:24 PM

Bring them up on a slow charge. They should be fine.

altamont · 12-13-2008, 10:27 PM

I just plugged the AS to shore power and left it at that. I had to leave town. Will the unit bring the batteries up OK?

Airslide · 12-13-2008, 10:35 PM

Well, I think i would use my external charger thats designed to bring a battery up to a proper charge. I have a trickle charger i use for this type of thing. The charger / inverter in your trailer will do this but its really designed to work with fully charged or weak batteries. It might be rough to bring them up when completely dead. I bet it works out fine in the end but I would imagine there will be folks that would disagree.

68 Overlander · 12-13-2008, 11:03 PM

If you have it charging now, that is good. Don't worry too much until you see what if anything happened.
When you get back, remove the charger and do a hydrometer check on the cells. You might get lucky. You can also have them load tested and go from there.

SteveH · 12-14-2008, 07:23 AM

A total discharge usually doesn't kill the battery immediately, but it usually does shorten their life expectancy.

Mikethefixit · 12-14-2008, 07:36 AM

Make sure you check the water in those batteries if they are service type.
Add only distilled water to the cells. Make sure each cell have water above the plates.
U should be fine But if ya have the time Id bring them up slowly with a regular battery charger.

Silvertwinkie · 12-14-2008, 07:39 AM

Doing it once simply degrades the battery, won't kill it. I did it 3x and they still worked, but didn't last all that long after each following dead event.

I decided not to replace them until I got a 3 stage charger. Now that I have a 3 stage installed, I'll be replacing the batteries (which I've used for 5 seasons). In all honesty though after the 4th season they were degraded enough to be fairly useless if I had boondocked any duration over a few days.

ROBERT CROSS · 12-14-2008, 08:57 AM

As others have said, it is always better to use a three stage charger designed to charge, maintain and recondition

Iv'e used this with great results the last three seasons. VEC1093A. Just desulfated, and now have the coach batt's on the maint charge. (out of coach in basement)
Good deals on the net.

Vector Manufacturing VEC093 VEC1093 VEC1093A VECo93 car battery charger

Gene · 12-14-2008, 11:19 AM

Don't the newest trailers have a three stage charger? Altamont has a 2007, but Bob and Silvertwinkie have 2003 and 2004. Did they start installing 3 stage chargers only recently? I would think the internal charger would be ok, but a separate trickle charger better. Even then you should take the covers off the cells to prevent gas buildup in the batteries and before charging, check the water in the cells.

When traveling, I wonder if the TV alternator would charge a dead battery as I've always believed it will not charge the TV battery if it's dead. What about the generator option if the trailer batteries are dead—you can charge through the 120 v. system or directly to the batteries with the 12 v output. If you use the 12 v output I guess the batteries would have to be watched because you could overcharge unless there's a 3 stage unit in the generator, so it might be safer to charge through the 120 v. system. So many questions….

Gene

ROBERT CROSS · 12-14-2008, 11:49 AM

Our 03 Classic does have a 7400 series Parallax 3 stage. It has worked satisfactorily for the last several seasons. BUT... The batteries were one of the first things we had to replace. When I asked the dealer about it I found out that the coach had been plugged in for at least a month before we picked it up and I figured that was the reason they were boiled dry. Interstate did replace them under warranty. Ever since I have been a little gun-shy, and check them frequently when on shore power.

Will the tv charge the coach battery, in my experience, not very well. In our 63 with one battery it took forever for a 145amp Burb alternator to even make a dent in a 11.5v coach battery.

Our Honda 2000 does a good job of charging, when the coach needs a "real" charge I connect directly to the gen. Plugging the coach into the gen will bring it back some but I never use it that way when the batteries are below 12v.

Be safe and check levels often on shore power.

Gene · 12-14-2008, 12:04 PM

I have generally kept the trailer plugged into shore power and over several months they have needed a little water, but not much. They lose more water in the summer regardless of when and how the shore power is used. My experience with a 1,000 watt Honda gen. is that it doesn't charge too fast, but will do ok over an hour or so plugged into the 120 v cable. I have thought of looking for a shorter cable since it's a long, long way (about 50 feet) from the male plug to the converter and then to the batteries.

I have unplugged it for a while to see what happens to the charge. Right now there's a couple of inches snow on the solar panel, so this would be a good time to see what the battery voltage is.

Gene

Inland RV Center, In · 12-14-2008, 12:20 PM

Quote:

Originally Posted by ROBERT CROSS

Will the tv charge the coach battery, in my experience, not very well. In our 63 with one battery it took forever for a 145amp Burb alternator to even make a dent in a 11.5v coach battery.

Our Honda 2000 does a good job of charging, when the coach needs a "real" charge I connect directly to the gen. Plugging the coach into the gen will bring it back some but I never use it that way when the batteries are below 12v.

Be safe and check levels often on shore power.

Aproperly wired charge line, should provide about 40 amps per hour to charge the trailer battery.

The size of wire, connections, terminlas, all have an effect on voltage drop.

Tow vehicles from the last 20 years, should all charge the trailers battery, in short order.

Of course, double that time if you have 2 trailer batteries.

Andy

ROBERTSUNRUS · 12-14-2008, 11:23 PM

Hi, The best way to recharge any totally dead battery, [FLA] flooded lead acid, is to slow charge it. You need to charge dead battries at 2 amps or less for 24 to 48 hours. Fast or high amp recharges, cook batteries and or burn out battery chargers.

Inland RV Center, In · 12-15-2008, 06:50 AM

Quote:

Originally Posted by ROBERTSUNRUS

Hi, The best way to recharge any totally dead battery, [FLA] flooded lead acid, is to slow charge it. You need to charge dead battries at 2 amps or less for 24 to 48 hours. Fast or high amp recharges, cook batteries and or burn out battery chargers.

And make super sure that the polarity is followed.

A dead battery can easily be reverse charged.

A showed many students what the result of that can be, especially when you installed a reversed charged battery in a circuit with correctly polarized batteries.

BANG, SMOKE AND FIRE, INSTANTLY.

Andy

Beginner · 12-15-2008, 07:03 AM

altimont
The best way to charge completely dead batteries is with a trickle charger (2 amps or less until fully charged (no longer drawing current) of 48 hrs atleast. Always be sure you have the polarity correct (red to +, black to -) cach cell full to fill ring (app. 1/2 to 1 inch depending upon maufacturer) and in a vented area (not around a gas appliance (gas water heater) with an open flame.
If you battery charger has an apm meter you might notice that when you hook up the battery charger to the battery, the battery might not draw any current (zero amps), often a dead battery will start out this way. Leave it for several hours and check back on it. The current will eventually come up.
Beginner

Inland RV Center, In · 12-15-2008, 07:12 AM

Quote:

Originally Posted by Beginner

altimont
If you battery charger has an apm meter you might notice that when you hook up the battery charger to the battery, the battery might not draw any current (zero amps), often a dead battery will start out this way. Leave it for several hours and check back on it. The current will eventually come up.
Beginner

And if it doesn't come back up, have a beer and buy a new battery.

The rule is "never, never, ever", allow a lead acid battery to completely discharge.

Andy

altamont · 12-18-2008, 10:11 AM

Well, I got back to town and the battery charge meter reads 100%. Maybe I won't have to replace the batteries right now after all. I was sort of hoping they were toast as I want a couple of AGM's. Very expensive though and Christmas for 6 kids, 6 spouses and 12 grandkids is getting pretty expensive.

Airslide · 12-18-2008, 12:11 PM

Glad it worked out.. it usually does.

have a Merry Christmas..

Gene · 12-18-2008, 12:34 PM

Quote:

Originally Posted by altamont

Well, I got back to town and the battery charge meter reads 100%. Maybe I won't have to replace the batteries right now after all. I was sort of hoping they were toast as I want a couple of AGM's. Very expensive though and Christmas for 6 kids, 6 spouses and 12 grandkids is getting pretty expensive.

"6 spouses"?? All at once?

I suspect mine are ok too and having the same "toast" desire. I've wanted to check the specific gravity in the cells, but since last Saturday we've had one snow storm after another (16" so far) and today it's blowing hard and snowing off and on and supposed to stay this way through Christmas. I can't face checking the batteries in this weather. One week it's in the 40's every day, dry as dust and sunny, and the next, mid-winter. You'd think I lived in Colorado.

The voltage on the solar panel has dropped from 12.8 to 12.6 with shore power unplugged and the panels covered with snow. That amounts to 100% I think. Some energy gets to the panels through the snow (.1 or .2 v when I've checked) and pretty much is a trickle charge.

Gene