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jgmace's avatar
jgmace
Explorer
Dec 14, 2016

House Batteries Dead

I purchased a 2000 Winnebago Ultimate Freedom Class A this summer. We plan to use it during the January - April time frame. I live in a Condo complex so have to store it offsite. I have been going down ever couple of weeks to start the coach engine and generator. After a 3 week period I started the coach but found the house batteries dead. I replace the batteries and 3 weeks later they were dead again. I obviously have something depleting the batteries, even though I hit the 12v isolation switch on the dash and verified no 12v power. My question now is, what is the best way to jump start the generator to recharge the house batteries. I have no ability to plug into house current.

Apreciate ny help you can offer.

J
Class A

17 Replies

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  • doxiemom11's avatar
    doxiemom11
    Explorer II
    Dec 15, 2016
    New batteries are not always fully charged when you get them. Did you make sure they had a full charge? We stored our MH thru a winter in MI with both engine and chassis battery switch to off. 6 mo later we turned switches back on and everything worked and it started right up. Are you sure the new batteries were installed and connected together properly?
  • jorbill2or's avatar
    jorbill2or
    Explorer II
    Dec 15, 2016
    If you have to leave it with no power .. disconnect the positive cable from the battery .. no more parasitic drain possible and no more dead battery ..it's a little more work but it does work and you won't be killing anouther set of batteries.
    Put a outside charger on the batteries or remove them and have them tested and charged .. unlikely you killed them with one full drain but anything is possible
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Dec 14, 2016
    jgmace wrote:
    OK, I let it run for about an hour this afternoon. I tried the switch you mentioned, but no luck. Perhaps I didn't hold it down long enough. I'll try it again and hold the bypass switch down for a while before attempting to start the generator.


    Let's back up a bit please.

    Obviously your house batteries are NOT charging when they should be.
    THAT is more likely the real problem instead of a parasitic drain (but it could be a combination of both).

    There is a "battery solenoid" which is responsible for connecting the two batteries together when they should be; while the main engine is running and when you push the "emergency battery" switch.

    You need a meter to do some voltage tests.......or you need to take it to a shop for testing and repair. IIRC the replacement of my battery solenoid cost me around $100 at a shop.
  • jgmace's avatar
    jgmace
    Explorer
    Dec 14, 2016
    OK, I let it run for about an hour this afternoon. I tried the switch you mentioned, but no luck. Perhaps I didn't hold it down long enough. I'll try it again and hold the bypass switch down for a while before attempting to start the generator.
  • Mandalay_Parr's avatar
    Mandalay_Parr
    Explorer
    Dec 14, 2016
    Possibly you have a Battery Boost switch on the dash that ties both battery systems together. Must hold it down while starting generator. That switch may have another name.
  • darsben1's avatar
    darsben1
    Explorer
    Dec 14, 2016
    If you start the rig then you should be able to start the genny in a few minutes.
    Engine alternator should charge house batteries
  • DrewE's avatar
    DrewE
    Explorer II
    Dec 14, 2016
    Start the main engine, and let it run for maybe a minute...then start the generator. Assuming your battery isolator is working decently, this probably would be enough.

    If you have an emergency start switch for the main engine, it might also let you start the generator as it simply connects the two battery banks together when you press it down. Often it's the same contactor as the battery isolator system to bridge the two together.

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