u/Bfsst27

Background context: the electrical system has been set up (professionally) since December (5 months) and was left turned on most of the time to keep the fridge running and batteries being used. There is 460w single solar panel and two 200ah batteries, and living in Ireland where it is cloudy and raining most of the time, as well as driving the van only once or twice a month while converting it, it still remained fully charged and at one point even began getting over-voltage beeping at 14.4 before changing settings on the shunt app. The resting voltage usually stayed around 13.8 for that entire time.

About 4 days into bringing the van into mainland Europe which included driving over 15hrs and being in almost constant sunlight, during the evening we realize the fridge had an error code which led us to realizing that the voltage was showing to be around 11.8 volts despite our app stating the battery was at 96% charge. On this day in particular our electric hob was used for about 20 mins in th morning and 20 mins in the evening, and besides the fridge constantly running (12v hookup) the only other things that were plugged in was our starlink and laptops charging for a couple of hours (using 2000w inverter charger). With the amount of solar and driving we were doing, our system should be lasting for days especially if it is getting some level of recharge from the solar to make up for what we are using.

We adjusted the settings in our app after researching and realizing that it may not have been synced up properly and probably wasn’t really 100% charged when it said it was, drove for a few hours and watched to make sure that the dcdc and solar was also bringing in appropriate levels of wattage so that the battery did rise back up to what we thought was 100%, although we notice that the voltage wouldnt rise above 13.3 at any point despite voltage being higher when the van wasn’t being used in Ireland. The voltage would fluctuate on our usb outlets when things would be plugged in (ie phone charging) and could go down to 12.8 or 12.9 while charging…it seems like 13.1 would be the average of where it would float most of the time over the next couple of days since we noticed the first issue and recharged. We used our portable gas hob for breakfast and dinner for a day or two as well so to not be drawing more energy than just the fridge and starlink for work.

Yesterday we were parked up for the entire day with no driving, but it was fully sunny with no clouds for around 12 hours and showed that the solar panel was bringing in almost full wattage of what it’s capable of, and the batteries were apparently fully charged from the day before when we drove for a few hours and had full sun as well. Again we used our hob for 15-20 mins in the morning and in the evening and charge laptops for a couple of hours, had the fridge running and our starlink. During the day and the couple of days before our max voltage readings were at 13.5 and 13.6…When going to bed we realized the usb outlets were showing 12.1V and the mppt/dcdc charger controller had a red light on the battery which indicates low voltage. Turned the batteries off for about 30 minutes in the morning as we didn’t want the food in fridge to go bad overnight and since this morning the voltage rose to 12.4 and has been floating there as it’s a bit overcast so far and receiving less solar. We are stumped as the what the issue could be and are meant to be living in the van full time for the next 6 months which will include mostly off grid and campsites only once a week. Not feeling the most optimistic that this is happening just a week into our trip and looking for any sort of help that can fix these issues 😢

Set up:
Solar: single panel 460w
Batteries: two lifepo4 200ah batteries in parallel
DCC50S 12V 50A DC-DC On-Board Battery Charger with MPPT(New Version)
2000W 12V Pure Sine Wave Inverter Charger