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Old 06-29-2015, 01:03 PM   #1
2 Rivet Member
1969 23' Safari
Mohnton , Pennsylvania
Join Date: Nov 2014
Posts: 43
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Battery question

I have some battery questions. The trailer still has a very old battery in it and its time to replace it. I am assuming I need the battery due to the electric brakes and the break away switch, the battery would power up the brakes at that point?

If it werent for the brakes I probably wouldnt replace the battery at this point. were only going to be at campgrounds this year and will power up that way once there.

What size is this battery and were do I find something this big?
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Old 06-29-2015, 02:10 PM   #2
1974 27' Overlander
danville , New Hampshire
Join Date: Feb 2010
Posts: 28
battery size

If you look at the battery the Group number will normally be printed somewhere on a label. Group 24, 27, or 29 are most common. If you are not able to find a label with the group number take the dimensions and go to wally world (or your prefered vendor) and get a battery that is the same size.

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Old 06-29-2015, 02:16 PM   #3
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2006 23' Safari SE
Lexington , Kentucky
Join Date: Dec 2012
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The brakes are operated by engaging electric magnets. In the event that your trailer becomes separated from your tow vehicle (TV) the battery provides that power to stop, since it's no longer coupled to the TV. Most states require that safety feature so you'd need a battery to make it work.

The replacement battery/batteries would depend on your current battery box size, number of batteries and configuration. (It takes 12 volts so that could be 1 12 volt, 2 12 volts in parallel or 2 6 volts in series. At minimal, you'll need 1 12 volt, group 24 battery fully charged. It should be a deep cycle battery, not ignition battery. Home Depot, Walmart and others carry low cost batteries, take your old one for the exchange.

Rich & Yvonne
2006 Safari SE -Dora-
2004 4Runner SE
Most of us don't know exactly what we want, but we're pretty sure we don't have it. -Alfred E. Neuman
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Old 06-29-2015, 02:22 PM   #4
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1973 21' Globetrotter
Houston , Texas
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Just a few other things to think about--many of the items in your trailer run on 12V. These are typically the ceiling lights, any vent fans, bathroom fan, etc.. YOu will get 12V with your converter plugged into the 110V AC, but some converters require a battery in the system. If you are still using your old "Univolt," you might consider getting a modern replcement as the old units are notorious for boiling batteries.

Good luck!
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Old 06-29-2015, 02:26 PM   #5
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1974 Argosy 20
2014 20' Flying Cloud
Kooskia , Idaho
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If you are not going to be operating dry, with no hookups at all this year (or any time) all you need is the smallest battery at a reasonable price. I would recommend a group #24 Marine type battery from Walmart/Sams Club/Costco. Minimal cost and would do the break away switch, brake issue just fine. It does not even needs to be a deep cycle type to provide just the break away function just fine, but the cost of a marine type (semi deep cycle) is about the same as any regular automotive battery, so I would get one of those.
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Old 06-29-2015, 03:30 PM   #6
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2000 25' Safari
1999 34' Excella
Davidson County , NC Highlands County, FL
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I've been using a Walmart marine battery in my Safari. That was what was in it when I bought it. They cost a little over $100. They usually last 2-3 seasons. I camp often where there are no hookups. The single battery in my Safari will easily go two days boondocking, when not using the furnace. When using the furnace in cold weather I charge it every evening for about 2-3 hours.

There is a smaller one at Walmart that would do what you need, for about $65.
2014 Silverado LTZ 1500 Crew Cab 5.3L maximum trailering package
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Old 09-15-2015, 01:22 PM   #7
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A deep cycle marine battery is what we went with last year. So far so good. I did have to replace the univolt unit this year. The way we found out the univolt needed replacement was the hard way - when we were on our way home from Tucson earlier this year we stopped in Las Vegas, NM overnight. It got down to 15 degrees or so that night. That was the night the univolt unit went out. No problem? Well, the furnace fan drained the battery (yes we were hooked to shore 120V service - to Belgedhel's point above) and quit running after about an hour and no lights except the 120v lights. Now I have a new univolt unit + a catalytic heater which requires no electric and a fast connect to the propane supply off an LP hose which was added at the furnace under the sink - we can't risk being out in the cold with no furnace capability. Also - what if the power goes out in the trailer park you are in? It does happen
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Old 09-15-2015, 01:48 PM   #8
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2019 23' International
Portland , Oregon
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Costco Group 24 around $70 with core. It's an Interstate battery with different color and graphics
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Old 09-16-2015, 06:28 AM   #9
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1969 23' Safari
Mohnton , Pennsylvania
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Well I ended up buying a marine battery and marine battery box. I traded in the 40yr old large tractor battery. I still have the univolt system for now, dont fix what isnt broken yet.
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Old 09-16-2015, 06:57 AM   #10
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1983 27' Excella
Walnut Grove/Laguna Woods , California
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In this case, it's good to fix what isn't broken. Replace the univolt with a modern unit. Your new battery will love you for it.

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