Can I safely use shore power to charge a chassis battery?

Ericb760 · 05-16-2019, 03:48 PM

In diagnosing why my Kwikee steps quit working I discovered that they are wired to the chassis battery, which, oddly, seems standard. I also discovered that the chassis battery would not start the engine without a boost from the house batteries.

Question: Can I use the 110V outlet in my basement to plug in a trickle charger to attach to the chassis battery while I'm on shore power?

Phil-T · 05-16-2019, 03:58 PM

Yes you can, but your converter should be charging the chassis battery.

WinnieView · 05-16-2019, 04:00 PM

There should be no reason that would not work. You might want to consider installing a Trik-L-Start charger in the future which will connect and keep the chassis battery charged anytime the coach batteries are being charged.

Ericb760 · 05-16-2019, 04:04 PM

Quote:

Originally Posted by Phil-T

Yes you can, but your converter should be charging the chassis battery.

Hmmmmm, okay. Well, either the battery is too far gone or the converter isn't charging it. I do have a 110V trickle charger, but the only 110V available to me is onboard. I just want to make sure I'm not crosswiring anything if I use it. My wife would neuter me if I burned her new toy to the ground...

Phil-T · 05-17-2019, 04:32 AM

Put a multimeter on the battery and read the voltage with no shore power connected. This will give you an idea of the battery condition. Now connect the shore power and read the meter agasin, if being charged by the converter, then voltage will/should be 13v +.
Guess it's possible your converter does not charge the chassis battery.
Same procedure while engine is of, then running will tell if the engine system is charging that battery, it should be.

Wayne M · 05-17-2019, 07:08 AM

Eric, My 2008 WInni had the same problem of battery drainage when in storage. The trickle charger they have installed would not keep up with the demand of the parasitic current draw.

I called Winnebago after several months of this happening and the reply was to turn off the step as there is more current draw than than the system can provide for re-charging. Once I did that I never had a problem again when it was plugged in at my storage area.

Also they said to leave the disconnect switches ON, as the inverter needed them to be on in order to charge. Turning them off disconnects the charging system.

With all that said, remember it was my 2008, but even now with my 2015 I leave the steps off when not rolling down the road. I typically turn them on at my first potty stop or fuel stop to prevent anyone pulling in alongside from hitting them but once at a CG, home, or in storage they are always OFF. It may or may not help with your problem but what can one little switch hurt by turning it off.

Good luck and let us know what you find.

In direct response, yes, if you are plugged into a pedestal or 110v anywhere then the RV Receptacles can be used to plug in and charge the batteries. You could also plug directly into the pedestal or home 110v to charge.

FYI Info: Winnebago told me that the steps operate on an electronic current limiter switch. This switch always has current supplied to it and may be more of a current draw than the trickle charge can provide.

luvlabs · 05-17-2019, 09:37 AM

Quote:

Originally Posted by Phil-T

Yes you can, but your converter should be charging the chassis battery.

Simply not true in most coaches. Your chassis battery will be charged by the alternator but not the converter (which will only charge the house batteries). In new coaches, the chassis battery is often charged but not in one of your vintage.

Suggest you get an Amp-L-Start as it can provide more charging current than the Trik-L-Start.

Ericb760 · 05-18-2019, 07:20 PM

Battery is at 12.3 after being on the trickle charger for a full 24 hours. I am beginning to believe I have found the problem.

Kayak73 · 05-18-2019, 10:27 PM

Before you jump check specific gravity and put that thing on a real charger. It needs more than a trickle to get back healthy. If it won't charge on a good real charger then yeah, you found one problem. The other one is needing the Amp-L-Start because it will provide a lot more amps to charge the chassis battery.

millsrv · 05-22-2019, 06:34 PM

While on this subject it is worth mentioning that 07 my Winnebago Voyage (and many others) that the slides are powered by the chassis battery only, not the coach batteries. I always have the engine running when moving the slides. Low voltage is the number one cause of slide motor damage. Besides when the engine is running all of the batteries are connected together. I pull into my camping spot, put down the levelers, put out the slides, and then shut off the engine.

NeilV · 05-23-2019, 05:38 AM

Quote:

Originally Posted by Phil-T

Yes you can, but your converter should be charging the chassis battery.

On many/most coaches the converter only charges the house batteries and not the engine battery so for long term storage you have to use the battery disconnect to prevent parasitic drain on the batteries and consider a larger solar charger or installing a float charger of some kind on the engine battery.

The engine and house batteries have different charge rates and the isolator for charging is usually setup to switch charging from engine to house batteries when charging from the engines alternator. When boondocking for extended periods of time this can present a problem since most generators start from the engine battery making it so starting the generator repeatedly can run down the engine battery far enough that it will no longer start either the engine or the generator making it so that if your house batteries have also run low that you are really stuck unless you also carry a fully charged emergency jump starter or portable generator.

jcurtisis · 05-28-2019, 08:36 AM

Quote:

Originally Posted by Ericb760

In diagnosing why my Kwikee steps quit working I discovered that they are wired to the chassis battery, which, oddly, seems standard. I also discovered that the chassis battery would not start the engine without a boost from the house batteries.

Question: Can I use the 110V outlet in my basement to plug in a trickle charger to attach to the chassis battery while I'm on shore power?

Ericb760: yes; that is exactly what I do: attach a trickle charger to the chassis battery to a 110v house plug (had one installed by my RV for just such use). Be sure you consult with the chassis manufacturer as to what trickle chargers they recommend. My Navion is on a Mercedes Benz sprinter van chassis and M-B had a specific model to use for my rig. Of course, it was cheaper to buy on Amazon....