Eddie, in your post you say "battery" and later you say "batteries".
Which is it? If it's a single battery, no wonder the battery was drained.
You need at least two deep cycle batteries to dry camp for more than two nights.
If you used the furnace for any amount of time, then the battery would've drained even faster. The furnace is the biggest power drain of all.
and Zoe the Wonder Dog(R.I.P.)
2016 PrimeTime TracerAIR 255, pushing an '07 Chevy Avalanche
Equalizer WDH and Prodigy BC