Winter battery maintenance

pianotuna wrote:
charge them. disconnect the positive posts. reconnect in spring or first trip.

times 2 exactly what to do

matter not what cable u remove + or -
If the battery is dead in the spring then replace it as its weak
no way a good fully charged battery should go dead after sitting 4 months or 6 months that has zero draw(disconnected)

Do your normal battery maintenance service, than as DrewE says, disconnect the negatives.

Next spring, you will likely need to jump the chassis battery with your car for a few minutes before trying to start the engine in the RV. Be sure to disconnect the car before trying to start the big RV engine to avoid damaging the car's alternator.

Once it's running, the alternator will bring the chassis battery up a bit, than start charging the house batteries too.

pianotuna wrote:
charge them. disconnect the positive posts. reconnect in spring or first trip.

It's better to disconnect the negatives.

Electrically it makes no matter either way, as an open circuit is an open circuit, no matter where it's open. However, it's generally safer to connect the negatives last and disconnect them first as accidentally shorting the wrench to the frame won't cause a short circuit that way. If you're undoing the positive with the negative still attached to chassis ground, hitting most anything metallic on the vehicle can easily result in a very, very hot wrench very quickly.

charge them. disconnect the positive posts. reconnect in spring or first trip.

Keep your batteries at 85% or more and you are good to -67 per Trojan. See http://www.trojanbattery.com/pdf/WP_DeepCycleBatteryStorage_0512.pdf

Instead of a dashboard unit consider a real solar system for camping and storage.