Forum Discussion

chrisandoctavia's avatar
chrisandoctavia
Explorer
May 09, 2016

Flat Batteries

We are the owners of a 2007 Itasca Impulse that has done relatively low mileage (just over 38K), and that is in pretty decent condition

On March 24th we had the local RV dealer who we have used before do some work on the RV - amongst which was to fit heating pads to our waste tanks. These are DC powered

There are two switches above the main panel - both of which were off when we parked the RV in the RV yard

We have just been to the RV to get some coats and have found both the house batteries and the coach main engine battery are dead

Even though the power lights for the heating pads were off - could there have been a problem here and the battery got drained?

We know we have a problem with our heating thermostat which even when the lever is set of "Off" - still kicks in the heating blower fan if the temperature falls below a certain level (we know we need to get this attended to....), so this might be the culprit for the house batteries, though I didn't think it had been that cold since the end of March

Have any of you been in this situation where you have found those batteries dead after leaving the RV for just over 6 weeks (I forgot to set the battery cut-off switch

If the house battery drains - could it also drain the coach main engine battery as well?

We have Roadside assist and will get them to jump the battery and make sure all are recharged - but wondered if anyone else has ever had this issue

Thanks for any advice you can give

Chris
Class C
  • crasster's avatar
    crasster
    Explorer II
    May 12, 2016
    Get a battery minder desulphator. They are completely fantastic. They really do fix weak batteries.
  • Bordercollie's avatar
    Bordercollie
    Explorer
    May 11, 2016
    The starting battery can self-discharge in six weeks. You need to connect a smart trickle charger to the starting battery and connect it to a 110volt
    AC source. You must also make sure that there are no lights left on in storage compartments, etc. Google "Battery Minder" Note: Most RV's are not equipped to charge the starting battery when connected to shore power, only the house battery is charged unless a special device is installed. Google "Trik-L-Start"
  • time2roll's avatar
    time2roll
    Nomad
    May 10, 2016
    Odd for the chassis battery to drain in six weeks. House battery is a given if you don't use the switch.

    To really verify what is going on you need a DC clamp-on ammeter. About $50 at sears.
  • DrewE's avatar
    DrewE
    Explorer II
    May 10, 2016
    chrisandoctavia wrote:
    Do any of you know if having the two "house" DC batteries drain would eventually cause a drain on the main coach engine battery?


    They should not, generally speaking. If something is malfunctioning or miswired, they could.

    It's also possible (and in my estimation more likely) that the parasitic loads on the chassis battery could discharge it independently of the house battery over the course of six weeks, particularly if the chassis battery is relatively old or wasn't fully charged to begin with. If the work involved leaving the front doors open for a length of time, just the dome light (assuming you have one, or a light of some sort wired in its place) would easily be sufficient to drain it.
  • chrisandoctavia's avatar
    chrisandoctavia
    Explorer
    May 10, 2016
    Thanks all for your replies - much appreciated

    I'll probably get the dealer to take a look at it once we've recharged the batteries.....
  • pauldub's avatar
    pauldub
    Explorer
    May 10, 2016
    If the electrical system is working properly, the house electrical loads won't drain the chassis battery. If the battery isolation relay is faulty, the house could drain the chassis battery.
  • chrisandoctavia's avatar
    chrisandoctavia
    Explorer
    May 10, 2016
    Do any of you know if having the two "house" DC batteries drain would eventually cause a drain on the main coach engine battery?
  • Artum_Snowbird's avatar
    Artum_Snowbird
    Explorer
    May 10, 2016
    Certainly you have a rig that is almost ten years old. Have the batteries ever been replaced? I just put a new one in my boat that died over the winter, it was 11 years old.

    Each year they lose a little bit of their capacity to hold a charge, and with yours, they might have been OK if you had them charged and then disconnected them totally... or they might not at that age.

    Time for a Costco trip to get some new ones, and some learning about disconnecting I reckon.

    good luck
  • Toddupton's avatar
    Toddupton
    Explorer
    May 10, 2016
    In 6 weeks I would think all the other parisitic draws would kill batteries.

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