Forum Discussion

Land_Yachters's avatar
Land_Yachters
Explorer
Nov 16, 2019

Trickle Charging Chassis battery

I am new to everything in our new (used Tiffin 33aa) coach, but am learning fast. I just learned the battery charger is only connected to house batteries, not chassis batteries. I have power connected while sitting outside for the winter, but that won't help chassis power. I expect to be starting/driving on occasion during the winter months, just to become more comfortable driving it, and want to just connect charger to the chassis batteries. If you look at pic, in the upper right corner, there are 2 terminals, labeled chassis battery (+) and chassis battery (-). Can I just connect charger to those 2 terminals for trickle charging? Maybe I am overthinking this, but don't want to make expensive mistake.
  • Bobbo's avatar
    Bobbo
    Explorer II
    Nov 17, 2019
    garym114 wrote:
    Just make yourself a ring jumper, one wire, connect + of house to + of chassis battery.


    VERY bad idea. If you drain the house battery, you also drain the chassis battery and won't be able to start the MH to drive anywhere. The Trik-L-Start is a one way power transfer. It allows power to flow from the house battery (converter/charger) to the chassis battery, but does not allow current to flow the other direction. That prevents the house from running down the chassis battery. (It also doesn't let power flow from the house battery to the chassis battery if the house battery charge is lower than the chassis battery charge.)
  • garym114's avatar
    garym114
    Explorer II
    Nov 17, 2019
    Just make yourself a ring jumper, one wire, connect + of house to + of chassis battery.

  • Bobbo's avatar
    Bobbo
    Explorer II
    Nov 17, 2019
    When I had a Class C with a chassis battery, it did not charge from the converter/charger. I bought a Trik-L-Start and installed it on the solenoid that connected the two batteries together when I pushed a button on the dash. I put the source wire on the house battery lug. I put the destination wire on the chassis battery lug. I grounded the unit to the chassis. From then on, as long as the RV was plugged in, the chassis battery charged. The Trik-L-Start was secure in the electrical bay, out of sight. I bet whoever bought that RV 3 years ago still doesn't know it is there, but just assumes the converter/charger always kept the chassis battery charged.
  • Veebyes's avatar
    Veebyes
    Explorer II
    Nov 17, 2019
    If the batteries are all together it would be a simple matter to connect the starting battery in parallel with the house bank & give it a trickle charge that way.

    There are always ghost draws of power however small. The only way to make the vehicle completely dead is to physically disconnect the battery. It will still discharge. About 10% per month for a wet cell. 5% per month if you have AGMs.

    AGMs are more forgiving. My 5er was put away last week. It has a single 4D AGM. Battery was disconnected & won't see any attention till next April. My last AGM gave me 9 years service storing this way.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Nov 16, 2019
    First, are you assuming that the chassis battery doesn't charge when the coach is plugged in......or did you actually test it to be sure ?

    You NEED a multi-meter, for this and future questions/problems.

    Neither of my two units did either.....but they were supposed to and the fix was fairly simple and inexpensive. The bad "battery relay" caused the coach batteries not to charge when going down the road either.

    P.S. If you find that you do need a separate charger, it needs to be an automatic tender type and NOT a cheap trickle charger. The difference is important.
  • Lwiddis's avatar
    Lwiddis
    Explorer II
    Nov 16, 2019
    Plugin charging isn’t the only way for house or chassis batteries.

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