Open the VictronConnect app and select the MPPT 75/15 (or 75/10). On the main screen, you’ll see a dial showing solar output (watts). Below that, under “Solar,” you’ll see voltage and current—these tell you how many volts and amps are coming from the panels. For charging to occur, panel voltage must be at least 5 volts higher than battery voltage. When we test panels indoors at the shop, we often see about 12V from indoor light. In full sun you should typically see 20V+ (and charging current). If it’s daylight and you’re seeing under 12V, there’s likely a problem. Keep reading for more information.

If your panels have a smooth surface, you can stop here and contact us directly. If your panels have a pebbly surface (like a basketball), read on. We’ve been receiving reports of these panels failing. In the past, we installed (or shipped) warranty replacements from our stock—but we now believe those replacement panels may fail as well (one customer is on their fourth set). Currently, we are out of the pebbly panels and do not have any direct replacements available. We’re working with Sunflare to obtain improved replacement panels, but because these are a custom specification made specifically for us, this process will likely take several months. We know this situation is frustrating, and we are pushing Sunflare to stand behind their product so we can get you replacements as soon as possible.

We’ve placed and order for replacement panels will be in a container from Sweden leaving early August so we will likely see them mid to late September. These Swedish made panels should be of much better quality and have a higher efficiency. SunFlare’s tooling has changed, and each individual cell is now larger, which means that with our limited space on the roof we’ll be getting a lower wattage panel so that it will still fit on the roof. As with our current solar offering, we are expecting more actual output than the older panels due to better efficiency, shading tolerances, etc.

For transparency: while Sunflare was quiet and slow to respond, we began looking for an alternate solution. Starting in October 2025, we began installing solar panels from a different vendor on NEW trailers. If you NEED new panels sooner than August, we are able to offer the new panels this new solution is significantly more expensive

We are working diligently toward a long-term fix. In the meantime, we’re tracking failures in the order they occur so that, once we have a solution, we can send or install replacement panels as efficiently as possible. If you believe your solar panels have failed, please submit a Service & Maintenance Request form (bottom right on the Vistabule website).

Keeping your battery charged without solar panels – First and foremost, charge your battery with the onboard battery charger whenever possible by simply plugging in the trailer to shore power. Shore power provides the best, fastest and most robust charging to make sure that your Vistabule’s battery is truly fully charged.  A full Lithium battery should power the cooler/fan/lights and cellphones for 5 days. A second option is to use a portable power station capable of outputting 110v AC power to charge the battery just as you would at an electrical campsite or your home. You can then charge the power station while you drive or via solar panels at camp. As for solar, don’t forget about using a separate Zamp/GoPower brand solar panel plugged into the Zamp/GoPower solar port adjacent to the 110v/shore power plug. And finally in most cases your tow vehicle should be capable of charging while you are towing the trailer.