In RV park. Now have car to drive. Disconnect RV battery?

No need for Pea-ing matches here........

The OP is simply trying to decide whether to disconnect the chassis battery or not, and is probably open to other battery related maintenance issues. Best thing you can do is suggest to the OP specific products that will do the job.

Get a 120v powered battery tender, something that charges, watches battery voltage, turns off an on as needed to keep the battery fully charged, and probably has a desulfating cycle to help extend the life of the battery. Either run the tender off the power pedestal or an external receptacle on the MH and use a simple, cheap 16 gauge extension cord for that purpose.

The OP is not looking for million dollar ideas I suspect.

Northern Tool has a fairly highly rated Battery Minder that is 2 amp max, does a good job of keeping the battery charged and desulfating it. It comes with alligator clips and also adapters so it can be hardwired if desired. Its a little pricey at $80 but is a good unit. This will also be useful in the future when the MH is in storage and batteries need to be kept up.

http://www.northerntool.com/shop/tools/product_200483764_200483764

Charles

Or you can install a BIRD a Bi Directional Isolator Relay Delay

There are some brands that come from the factory with them already installed,Fleetwood products such as mine and some Winnebagos come from the factory with a BIRD and if the battery disconnect,on the power panel, is left on it will connect both batteries when not on shore power or generator.

It operates by sensing the voltages on both batteries.
When either of these voltages exceeds 13.3 volts for
approximately 1 minute, which happens when either battery
is being charged, the control will close the isolator solenoid,
connecting the two batteries together, charging them both.
(Normal charging voltages are from approximately 13.8 to
14.4 volts.)
After the solenoid has been closed, the system continues to
sense the voltage. If the ignition switch is off and the battery
voltage drops below 12.8 volts for approximately 1 minute,
which might occur when the converter is heavily loaded,
the solenoid is opened to prevent the chassis battery from
being discharged by the coach loads. When the voltage goes
above 13.3 volts again for approximately 1 minute, the solenoid
closes again. Thus always keeping the Coach as well as Chassis battery charged. Regardless of the parasitic draws on the chassis battery that run it down while sitting unused.

+1 for Trik-L-Start

I have this item and it works perfectly.

:)

A simple trickle charger will work but needs to be monitored and shut off when fully charged.
There are also trickle chargers with overcharge protection.
A smart charger is a better choice if it is to be left unattended for a longer period of time.
There are small solar, (relatively inexpensive) chargers that come with a controller, and in my opinion are a better investment. I would suggest one in the 40 watt range.
No matter which application is chosen, it is always advisable to monitor, and check water level.

Sam Spade wrote:

Sully2 wrote:

Even disconnected electrically...a SMALL (1 to 1.5 amp) trickle charger hooked to that battery wont hurt a thing....and the battery will be up to 100 percent when you need it most

Not exactly.

A trickle charger left connected indefinitely tends to bring the battery up to a full charge and then OVERcharge it and cause it to lose water.

What is needed is a smart, automatic battery maintainer (battery tender). That is NOT a trickle charger.

All of the small trickle chargers I ever had personal dealings with ....had enough "memory sense" to shut off after 12.5 volts!:S That way any sever overcharging never happened. And when does indefinitely
ever enter into any RV picture

I have an oldie but goody (which reminds me, I need to work on my signature.) 1985 Rockwood class C, 27'. Chevy. I never expected being plugged into shore power would charge the battery under the hood, but that would surely be nice.

It would be helpful if we knew the model and year of your motorhome. Many motorhomes prior to 2003 don't charge the chassis battery from shore power. Most of those after that date are supposed to. If yours is a newer model you may have something as simple as a failed isolation solenoid causing the problem.

If it's an older unit as mentioned I would have the battery tested before replacing it. If it's good and just gets drained too quickly it probably has a large a parasitic load. You could also have problems with the coaches charging system.

I was in the auto service repair business many years. I can't count the number of times people went to Kmart or Sears and purchased a new battery, only to have it dead in a couple weeks. In many cases it was the result of the alternator not charging the battery, either because it failed, or the belt was so loose it slipped under load.

At the price of batteries these days I would be sure you need one, and be sure the charging and electrical system are up to snuff to avoid ruining a new one.

Sully2 wrote:

Even disconnected electrically...a SMALL (1 to 1.5 amp) trickle charger hooked to that battery wont hurt a thing....and the battery will be up to 100 percent when you need it most

Not exactly.

A trickle charger left connected indefinitely tends to bring the battery up to a full charge and then OVERcharge it and cause it to lose water.

What is needed is a smart, automatic battery maintainer (battery tender). That is NOT a trickle charger.