The tow vehicle charging up the trailer battery is a relatively slow process. Running the truck for a half hour won't restore much of the charge.
You need to inventory **EVERYTHING** in the trailer that might be on.
- The heater you mentioned will pull down a battery that is not fully charged very quickly. The blower motor uses a lot of current.
- Go away for 5 hours with all the scare lights on and you'll likely have drawn it way down.
- Same for the interior lights. They draw more than you think. That's why so many of us have talked about LED conversions.
- Festus2 already mentioned the heater strip on the fridge, but it bears repeating. That will suck a battery down fast.
If the battery has been pulled way down, an hour or two of generator time to run the on board convertor is insufficient to restore a full charge to that battery. If you have a high capacity charger that you can connect to the generator, it will recharge faster, but still needs time.
Dry camping requires thoughtful electricity conservation by everyone in your group. It has to be a team effort. And it requires planned recharging that will bring the battery back up to full capacity every day.
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'11 Cougar 326MKS loaded with mods
'12 Ford F250 SuperCab 6.7 PowerStroke Diesel
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