Dry Camp Battery Life

I dry camped for two nights with a single 12v battery.  Frig on propane.  only ran the heater and the outside amber light. The battery drained to the point that frig died and the led lights would not operate about 4 am.  Zamp had me up and running soon after sunrise.  temps down to the low 40s /upper 30s outside. Thermostat on 68 deg. inside.

Is that normal?  seems like even a single battery should run the fan on the heater for 8 hours or more.

Texman

I am adding a second 12v battery to the existing battery.  ( i know dual 6v is better from this forum, but dollars ruled my decision)

I could see it going down if you had it running all night.I set mine to 60 when it's cold, I have 2 batteries and never had a problem. Did you run the refer on 12 volt while you traveled?

We just spent 10-days camping down to 29 degrees. When temperatures dropped into the 30s we (two adults and dogs) thought the heater only came on a half dozen times (Thermostat 75 degrees). Not even an hour total. If you have a Group 24 battery in good condition that should provide about 75 amp hours. I'm guessing that the heater pulls about 5-10 amps an hour. 75 amp hours should get you through a weekend. 

What was the charge status of the batteries from the start? "charged on the zamp, and charged during a 2.5 hour tow" mean nothing. How much charge? 5amps? 10? 30? per hour..

The stupid monitor on the wall is useless when boondocking. You need to know the actual voltage and charge status/state. Taking a battery to the point it won't light an LED ceiling light is bad, very bad, for the battery.

There are some easily overlooked loads on the 12v.. stereo, and antenna booster, are two of the biggest. Make sure they are off, and or the fuse is pulled for max off grid happiness.

You state the zamp had you all charged back up in the morning.. not possible. maybe what you saw on the stupid monitor, but is telling you system voltage, not battery SOC status. If you really took a 12v group 24, in good health, to 8 volts or less, the zamp panel would have to be 400 watts and in perfect conditions to bring that battery to 100% SOC in a full day.

the battery is a gas tank, yours holds 58 "gallons/amps", the portable zamp panels can "pump", about 4 "gallons/amps" an hour.

it said 7.5 amps was hopefully what it was putting into the battery.. That has nothing to do with how many amps may be, or are, in the battery, and no matter how good the sun, once 80% SOC is reached, the charge rate slows WAY down, it's just a function of how FLA batteries work.

To test the battery, charge to 100% allow to sit disconnected, with no load, for 6 hours, then test voltage. This avoids testing a surface charge.

SOC = State Of Charge.

Also note if the zamp is trying to charge the dead battery, and ANYTHING else is drawing 12v, that amperage is lost to the battery... also increasing charge times.