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SFVdave's avatar
SFVdave
Explorer
Nov 16, 2014

Problem charging House Batteries

My 2004 Ford E-350 V10 Class C has developed a problem with charging the house batteries. I have a Xantrex Battery monitor. My house batteries are 2 Group 24 batteries brand new, 2 weeks old. because I thought they were not charging when driving. Found 2 bad cells and they were 42 months old.
So the house batteries were replaced. I was at a full hookup camp ground for 3 days and the batteries should have been fully charged. We left yesterday and drove 2 1/2 hours to another CG with full hookups. The Xantrex battery monitor showed full when we arrived. This morning after a night hooked up to shoreline power, I disconnected the shoreline power and went in to check the Xantrex battery monitor. It showed 85% and 12.4 volts. I hit the wall panel tanks/propane and battery switch and it showed 2/3's. that's crazy, it should be full and 12.6 volts. I started the engine and it showed 14.2 volts and 10 amps on the Xantrex battery monitor and full on the wall panel of gauges. I drove for 6 hours and when I got home, it was 12.6 volts, fully charged.
Before I changed out the batteries, It would be fully charged when I pull out of my driveway and be down 10-15% after getting to the CG 6 hours later. Do I have a bad switch somewhere or could my converter charger which is an Intelli Power 45 amp with the charge wizard be the problem? How do I test?

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  • SFVdave's avatar
    SFVdave
    Explorer
    Nov 16, 2014
    New batteries are 2 weeks old. I used my Vector 40amp charger to slow charge them. Took 12 hours. When I installed them and they sat in the MH without the shoreline to charge them, they were still 12.9 volts 2 days later. It's not the batteries.
    I just went out to the MH. The Battery monitor reads 12.6 volts. I started the engine and it read 14.2 volts and is charging the house batteries at 8.2amps. this is after a 6 hour drive today.
    I did a test. With everything off, no shoreline power or engine running. I turned on the interior lights. I started the engine, no difference. I turned off the engine and hooked up the shoreline power. No difference in the light. They would always get much brighter when either the engine was on or the shoreline connected.
    I'm thinking it's the converter/charger or the Charge Wizard.
    And yes, I do have a good knowledge base for electrical.
  • Almot's avatar
    Almot
    Explorer III
    Nov 16, 2014
    Sagecoachdriver wrote:
    Could the Intelli power converter with the charge wizard be allowing the 110v shoreline to work for the 110 volt appliances like fridge(switches off propane), microwave and not let the 12volt system stuff get anything from the converter part.

    Converter supplies up to 45A all day and night, this is MORE than enough to run all your 110V devices and then put something into batteries. That is, if it works as it should.
  • SFVdave's avatar
    SFVdave
    Explorer
    Nov 16, 2014
    Almot, I am ruling out the batteries as I had this problem prior to the new batteries. Perhaps the charge wizard isn't keeping it in the high mode and dropping down to the maintenance trickle, but that is 13.4 volts. Can't be that.
    I can give Intelli-power a call Monday and ask. Must be it's not charging the batteries when it should.Seems intermittent sometimes the engine doesn't charge them while driving and some times it does. Same thing on shoreline power.
  • BFL13's avatar
    BFL13
    Explorer II
    Nov 16, 2014
    Very confusing to know how much the OP knows. Assuming nothing, not to insult, sorry, etc. BUT the main thing is that while charging you can't use the voltage to estimate state of charge. It can look "full" even though it is half full, because the voltage is over 13 while charging and 'full' is 12.7v.

    IMO ignore all gizmos that claim to report the state of charge. Just got to be a bunch of BS.

    So the usual problem is the batts were not fully charged when taken home from the store (shelf life they lose SOC), not top charged, run down more, not fully charged, and they are still in limbo.

    Or maybe not. Need more info from the OP who is no doubt, not as clueless as all that! Sorry again! :(
  • SFVdave's avatar
    SFVdave
    Explorer
    Nov 16, 2014
    Could the Intelli power converter with the charge wizard be allowing the 110v shoreline to work for the 110 volt appliances like fridge(switches off propane), microwave and not let the 12volt system stuff get anything from the converter part. thus any 12volt thing used like furnace or lights would draw off batteries. When I am dry camping on nothing is on except the fridge and parasitic drain, I have a draw of .6amps.
    How would I check?
  • Almot's avatar
    Almot
    Explorer III
    Nov 16, 2014
    Sagecoachdriver wrote:
    I started the engine and it showed 14.2 volts and 10 amps on the Xantrex battery monitor and full on the wall panel of gauges. I drove for 6 hours and when I got home, it was 12.6 volts, fully charged.

    It's always 14-something when alternator is running.

    Aldo, red-green Christmas lights on that wall panel I suggest you disregard, they are not to be relied on.

    Also, it should be 12.6 or 12.7 not when you have just finished charging, but 24 hours later and in absence of any loads. Take the cables off the battery, wait at least overnight and check the voltage in the morning. With multimeter like Mex said. It's too early to tell anything yet. Could be faulty battery, or faulty converter, or a short somewhere.
  • SFVdave's avatar
    SFVdave
    Explorer
    Nov 16, 2014
    Yes, a clamp-on amp multimeter and a cheap Harbor freight one. Both are digital.

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