Battery questions

[MDWine]

So last week we picked up our 'new to us' small 21ft TT.
We towed it to what will become the 'resting spot' between trips.
Everything was working on pickup, and an hour and a half later, we parked it.

6 days following, we went to the trailer to winterize. This location has no services, no electric... total boondock. no worries... towed it up to the dumping station, and drained all the tanks. Everything was going smoothly until it came time to pump anti-freeze through the lines...

Yep, no battery power. shucks!

I am no mechanic, certainly know very little about electrical systems, but it seems to me a fully charged battery should keep a charge over 6 days. Virginia has been cool, but not freezing. The battery was dead. I checked switches and breakers, everything seemed to be off. I can't locate anything that could have drained the battery.

My guess, battery at end of life. The previous owner says that he hasn't used the pump at all since last winter, they use a 'shore connection' all the time. I have to go back after charging to finish the job to see what happens. (wish I had jumper cables with me!)

Need a new battery, right?
Should I get a regular wet battery? a "deep cycle" marine?
Any input or suggestions would be greatly appreciated.
Please educate this old fart!

Michael

[Skip426]

If you need a battery, deep cycle is what you should buy .

Engine start batteries are built for a rapid high amp draw ( engine starter ) then to accept a full recharge.
Marine batteries , have different internal construction , to stabilize the cells during the pounding the battery would take in a boat in rough water .
Deep cycle , are made to provide , a low to med amp draw over a long period of time , before requiring a recharge , AND can tolerate being run down more often than the other two types.

[tpaul]

Do you have a battery disconnect switch anywhere? If that was off then I think you are right, probably just an old, dead battery.

What you replace it with depends on what you are planning for types of camping, how long without hookups, etc. Also what kind of space you have.

I've had deep cycle 12V marine batteries in the past and found that they sometimes wouldn't last through the night. (1 cold August night in Bryce Canyon NP). Since then I have switched to 6V batteries in series. Actually I now have 4 6V batteries in series/parallel. Also went with AGM. More expensive but less maintenance. And my trailer had a small solar panel for trickle charging so I don't have to take them in during the winter.

[Stan&Jacquie]

MDWine, I gather from your post that the trailer has only one battery, correct? My experience has taught me not to give up on a battery too soon. I would charge that battery with a 10amp charger until full and then continue to charge it for 24 hrs on a trickle charge (2amps). Reinstall it and cutoff power to the trailer for storage. Come back in 5-6 days and check the charge. If it is dead then dispose of it and replace it with 2 6v golf cart batteries wired in series to give you 12v total. Golf cart batteries will give you the most bang for the buck and can be bought economically ar SAMs Club or Costco. If you can afford more, do maintenance free AGM.s

[Stan&Jacquie]

PS. If the battery holds its charge (it will lose some charge. But shouldn't go completely dead) then work with it to see how it does. If you are going to do any boondocking, then two batteries are much better,

[Ray,IN]

Have your battery load-tested before buying a new one. IMO the best bang for the buck is a 100A marine battery for around $99.

[Arch Hoagland]

https://www.amazon.com/WirthCo-20128.../dp/B000CQFWLY

Install a cutoff switch and once you get a good working battery disconnect it when not in use.

[MDWine]

Thanks everyone for your comments.
Our trailer says it is rigged for solar, there's a plug on the side of the trailer.
Our trailer is stored in our boondock site, I'm looking for options to see if I can keep the battery alive when we there for the weekends. I will probably bring it home to charge for the next trip, but am thinking of a solar charger for daytime charging when camping.

It sounds like a deep-cycle is what we want, once I determine if this one is any good or not. Suggestions would be appreciated... I gotta lotta learnin' to do

[Mark_K5LXP]

Yep, batteries can be a bit vexing until you understand how they work. Most batteries don't die, they're murdered. You can declare the battery "bad" and replace it, but if there's something about how you're using or misusing it that caused the problem, you'll only repeat the exercise until you figure it out.

So do you want to test the battery you have? It's easy, but no point to it if the plan is to get a new one anyway.

Mark B.
Albuquerque, NM

[Piros1]

I I were you I would pull your battery and give it a good overnight barge and have it load tested. If bad replace with the largest deep cycle battery you can fit in your rig. Multiple batteries are always better especially if you plan to do a lot of boondocking. The suggestion of adding a battery disconnect for when you are not there and not connected to a power source is a real good idea. If you do t plan to use it much during the winter months then I would pull the battery out after you winterize it and store it in my basement or garage with a maintenance charger. Garage would be safer.

[ga traveler]

Was your heater thermostat cut off? If the thermostat called for heat, the fan in the furnace would come on and run the battery down. We ran into this many times at our dealership.

[Goodspike]

Originally Posted by MDWine

I am no mechanic, certainly know very little about electrical systems, but it seems to me a fully charged battery should keep a charge over 6 days.

I'm going to give a slightly different answer. I wouldn't make that assumption. There are a lot of parasitic charges draining the battery. I never leave my trailer sitting without using the battery disconnect unless I need the refrigerator to run.

Also, I wouldn't assume your tows gave the battery any significant charge. On some GM vehicles you need to be in tow haul mode or have the headlights on to get even a halfway decent charge and that doesn't compare to actually plugging in and charging. Other modern vehicles may have similar rules.

So before you go replacing the batteries I would give them a full charge and learn how they actually function in actual use. And disconnect when not in use. See what happens.

[MDWine]

Dang... battery power shouldn't be this complicated! lol...

So, only one battery for this little camper, I'm gathering that it doesn't do much.

I did buy a charger, hooked it up... positive to red, negative to black.
plugged in the charger and the LED says I have the poles reversed!
Wait... double check... red to +, black to -... it's connected properly
What the heck is that about?

Is it possible that it was hooked up to the camper incorrectly, and it was 'reverse charged' ? (I haven't owned this thing for more than 10 days yet!)

I'm bummed... I think I'll get a new deep-cycle so I can get my winterization finished, and start looking for alternative and additions.

I will install that cutoff for sure, along with a junction (?) box that will allow me to hook up other lights. I'd really love those rock lights under the trailer, and an LED strip under the awning!

It's gettin' cold here in Virginia, I gotta get the antifreeze into those lines this weekend!

Thanks for your comments, I still gotta lotta learnin' to do, and it sounds like a bit of work besides!

Michael

[Skip426]

Because RV manufacturers, very often used , black wire for positive at the battery , and white for the ground . Hooking up in reverse and damaging onboard electronics was quite common ( even reverse charging if a totally dead battery was installed ).
If the RV wiring to the battery is ; black and white wires; carefully follow the white wire , I'm sure you'll find it goes to the frame of the RV.
Be sure, which wire is pos/neg, before you install a new battery .

More info at;

The 12volt Side of Life (Part 1)