Mysterious Electrical Issues

Lots of questions...

The basics:

The lights, furnace fan and ignition, fridge controls and ignition, stereo, water pump, water heater thermostat and ignition all run off the 12v battery. The inverter gets it's power from the battery too, and runs some 120vac receptacles. There is an automatic transfer switch in the inverter which allows shore power to bypass the inverter to run those receptacles directly when shore power is available.

The battery is charged by the converter which is under the electrical panel which in turn gets it's power from the shore power inlet. The solar also charges the battery through it's controller. When towing the battery also gets charged from your tow vehicle alternator. So the battery has 3 charging sources.

The micro, a/c, and (I think) fridge 120V get their power from the shore power inlet directly but the fridge also needs 120v control power from the battery even when in 120vac mode.

Sounds complicated huh? Not so bad once you get to know the systems involved but definitely more complex that your home wiring.

So what you are seeing is a dead battery, that would leave outlets working long with the a/c and micro.

So why is your battery dead even though you have shore power? First place to look is to see if the converter operating. There are both a breaker for 120vac in and fuses for 12v out. Check those. It can be hard to see if the fuses are blown. A multimeter would really help with that and multiple (pun intended) other troubleshooting steps.

I suspect your solar is working fine but your converter isn't which would explain why you have 12v power in the afternoon but at night it dies. That still leaves the question of what is using all that battery power. While everything should work ok if you're on shore power and the converter is running I would still make sure all your 12v stuff and the inverter are off when your rpod is not in use, so you don't wind up with a dead battery again.

One thing to check besides all the obvious stuff we've talked about if you can't figure out what's using 12v power is to check to be sure the breakaway brake pin hasn't accidentally been pulled. That would drag your battery down quickly. Its the pin attached to the cable on the trailer tongue that you loop through the tow vehicle hitch and connects your rpod battery to the trailer brakes if your trailer gets unhitched.   

The ac to DC converter doesn't have anything to do with solar. We all have one in our rpods, whether we have solar or not. If you go with Li batteries you will need to change it because Li batteries are charged differently. This is very important for safety because under no circumstances do you ever want to overcharge a Li battery. A fire can result.

The solar charge controller manages charging from the solar module(s). so needs to be set up for Li, many charge controllers can often be set for either lead acid or Li batteries The solar charge controller only manages solar charging, not tow vehicle charging.

If you want to charge a Li battery from your tow vehicle you will need a DC DC converter for that. That's because normally when you connect your 7 way plug you are just connecting your tow vehicle battery directly to your trailer battery. That's ok as long as they are both lead acid but if the trailer battery is Li you need better control of the voltage you're charging at.

Is the fridge on 12v or 110?

The smaller 3.5 cubic foot fridges are all 3-way.  On the newer pods with the larger fridges they are all 2-way, either 120 electric or propane.

Update and two questions

I’m still having this issue, and still have not managed to track down the source. The converter is working properly, assuming the troubleshooting instructions in the manual were correct. The converter is in fact sending 13.6 V to the battery as designed.

At this point I have two additional questions.

One: does the power INverter (not converter) have anything to do with the battery draining too quickly? A Facebook group I follow had a post that indicated if the inverter is turned on the battery will drain VERY quickly. I turned the inverter off a week ago and so far I haven’t noticed any effect.

Two: Is there a minimum amperage size needed on the battery? I looked briefly and didn’t see one, but I’ll keep looking. I ask because I disconnected the battery tonight and took it up to AutoZone to have them test it, and they said it was not charged enough to test (it was only at 16%). This would make sense if the battery is only being charged by the solar panel, because it’s been overcast and raining all day. A gentleman at Auto Zone overheard my question and came forward to peek at the battery and suggested it was too small to run much of anything at all because it was only a 500 amp “super start” battery. He thought I would need a 750 amp battery.