RV Batteries

[Grapehound]

I just bought my third deep cycle marine battery in three years for my Rockwood Fifth Wheel. They keep going dead. I bring them indoors in winter and keep them connnected (plugged in) in the RV all during the camping season, even when I am not camping. I treat my batteries better than I treat my wife!

I had a battery guy tell me that the trickle chargers cannot charge the heavy plates in the deep cycle batteries so you have to plan to recharge them on a big charger and not by trickle charging, or by battery maintainers (which I haven't used) or even by just keeping your RV plugged in.

We took a three day camping trip last weekend after I had fully charged my new battery to 100% on the big charger. Now that I am home it is down to 50%, even though it was charging on the way down (140 miles), it was plugged in the whole time camping, and charging on the way home.

Do I need to fully charge the battery with my 6 amp charger after each camping trip?

Larry

[Super_Dave]

Smart charger or not, batteries left plugged in for any length of time will evaporate fluid and not charge correctly. Check fluid levels of wet cell batteries on a regular basis.

[ChuckSteed]

And you aren’t wanting to check an inverter. The proper name is converter and each performs differ t functions. Measure the DC voltage as stated and skip all this other stuff. If you don’t see 13 plus volts when hooked up then you have a converter issue and the batteries are not charging.

[ChuckSteed]

The battery guy meant well but is ill informed. You don’t need to use another charger on your RV battery provided th converter is working. The stock WFCO is ok provide its working

As already suggested measure the DC voltage with n shore power and the. With shore power

You should see about 12.6 and then 13.4 or better

If not then either the converter isn’t plugged in or when you replaced battery you reversed the leads for a second. If so you blew the reverse polarity fuses usually located on back side of converter

All of this is easy to troubleshoot and fix provided you have some basic mechanical skills

[Johnnybgood]

Check to see if your converter is working, and also check to see that you are getting a charge when your truck is running. You should be able to check at the plug in by use of a multimeter. You check the female plug on the truck by going to the 12 volt lead and then negative lead when your truck is running. Also, no offense intended, get a better battery. I have used Trojan 150 amp hour lead acid with fair results. This battery I have now is a Battle Born Lithium Ion 100 amp hour battery. It is expensive but it has a longer life then the lead acid.

[Grapehound]

partsman01 wrote:
I always check my charge rate when hooked up to power, and when I have the meter on the battery the amount of charge goes up when the inverter kick in, so you could check to see if yours at least varies the amount of charge between no load and then after leaving the lights on so your inverter kicks in to charge it.

I may just take the battery in to be checked (it's brand new) and the inverter system with the battery in the fifth wheel too.

[ppine]

May be an old crummy converter in your rig or a dated trickle charger.
Look out for phantom current draws.

[rrupert]

Have you checked to see if the charge line from your tow vehicle is putting out power? Test the battery voltage before hitched up, then check with the tow vehicle engine running. You should see an increase in voltage.

[theoldwizard1]

Grapehound wrote:
I just bought my third deep cycle marine battery in three years for my Rockwood Fifth Wheel.

Most "marine" batteries are NOT true "deep" discharge. They are dual purpose starting and trolling, therefore they are a compromise. True 12V deep discharge batteries are not common and likely can only be obtained at a solar energy store or possibly through a golf cart distributor. For a bit more money and a bit more space, you are better off buying two 6V golf cart batteries at Costco or Sams.

Grapehound wrote:
... keep them connnected (plugged in) in the RV all during the camping season, even when I am not camping.

If you suspect there is a possible short in the wiring either install a master disconnect switch or disconnect the batteries between trips.

Grapehound wrote:
We took a three day camping trip last weekend after I had fully charged my new battery to 100% on the big charger.

By "big charger" I hope you are referring to a smart charger that does 3 stage charging. If you are using it at home between trips, a 20-50 amp multi-stage charger is fine. It will have a maintenance mode so no trickle charger is required.

Grapehound wrote:
Now that I am home it is down to 50%, even though it was charging on the way down (140 miles), it was plugged in the whole time camping, and charging on the way home.

A proper full, recharge while driving is NOT POSSIBLE without special equipment.
Please read this.

[azrving]

Have you checked the electrolyte (water) level?

[2oldman]

Yes, a voltmeter should quickly reveal (or rule out) what's happening. Best tool in the box.

[time2roll]

Need a voltmeter to verify charging. 13.2 to 14.6 is charging. Steady 12.6 or less is not charging.

If it is a WFCO... get a different brand. Progressive dynamics, Boondocker, or IOTA.
You do not need anything big... 35 to 45 amps is fine plugged in with a single battery.

[toedtoes]

When you are driving to and from the parks, what are you running?

My first guess would be that you are running high power things off the house battery with an inverter while you are driving (residential fridge, air cond, etc.). That could substantially drain your battery just on the drive.

Another possibility is a phantom drain. When I had some work done on my engine, the new choke was accidentally hooked into the house battery - it was pulling power 24/7.

Those are both pretty easy to resolve. If they aren't the problem, then I'd look at your converter. It may be that the converter isn't converting the shore power to DC power - so your 12v system is running off the battery even though you're plugged in.

Or your charger isn't charging the battery when you're plugged in. The onboard battery meter will show a full charge when you are on shore power even if the battery is dead. So unplug and immediately check the battery - if it is low as soon as you unplug, then it's not charging properly.

[DavinD]

If you have a multimeter this is pretty easy to check. Measure the voltage at your batter while not plugged in. Next, plug it in and make sure the voltage goes up. If it doesn't, your converter is no working or is not connected properly.

[partsman01]

I always check my charge rate when hooked up to power, and when I have the meter on the battery the amount of charge goes up when the inverter kick in, so you could check to see if yours at least varies the amount of charge between no load and then after leaving the lights on so your inverter kicks in to charge it.