Anyone else had grief with a Victron SmartSolar 100/30 dropping connection to the VictronConnect app mid-session?

Mine's been playing up for the past few weeks. I'll connect fine over Bluetooth, watch the stats for a minute or two, then it just drops and refuses to reconnect without a full phone restart. Running a 200W panel into a 110Ah leisure battery on a Transit-based camper. Firmware is on the latest version (v3.14) and I've tried it on both my Android 13 Samsung and my old iPhone SE with the same result.

I've checked the obvious stuff — Bluetooth isn't being killed by battery optimisation on the Samsung, I've unpaired and re-paired the device, and I've even done a PIN reset on the MPPT itself. Short of that it seems solid enough, the charging figures look right and the battery's in good nick. It's more the monitoring side that's driving me mad because I like to keep an eye on state of charge when I'm parked up for a few days without hookup.

Has anyone cracked this, or is it a known bug with this hardware revision? I've seen a couple of vague mentions on the Victron community forum but nothing with a clear fix. Wondering if a dedicated Raspberry Pi running Venus OS might be the way forward just to get reliable data logging, but that feels like a lot of faff for what should be a basic Bluetooth connection.

@Chopper62 is it definitely a phone restart that fixes it, or just toggling Bluetooth off and on again? Asking because I had something similar with my 75/15 on the garden office build and it turned out the VictronConnect app just needed updating — I'd been putting off the update for weeks and once I did it the dropouts basically stopped.

Also worth checking — what phone are you on? I noticed mine was worse on Android 14 until I went into app permissions and made sure location was set to "allow all the time" rather than "only while using." Sounds daft but Bluetooth scanning on newer Android seems to need it. Is your MPPT firmware up to date too? Victron pushed a few updates last year that seemed to address BT stability.

Hey @Chopper62, had almost identical issues with mine last summer. Worth checking which firmware version the MPPT is running - there were a few dodgy builds around the 1.59-1.61 range that caused real headaches with BT stability. Open VictronConnect, go to the device settings and check for updates. Also, are you on Android or iOS? I found Android was far more temperamental, and keeping the phone screen on during the session rather than letting it sleep made a big difference for me. If updates don't sort it, try doing a full PIN reset on the Bluetooth pairing - delete it from your phone's paired devices list entirely and start fresh. Sorted mine out completely in the end.

Hey @Chopper62, just to add to what @EdGrant91 is getting at with firmware — also worth checking whether you've got the VictronConnect app itself fully up to date, as there was a period where the app and certain firmware versions weren't playing nicely together and caused exactly this sort of mid-session dropout behaviour.

One thing I'd try before even going down the firmware rabbit hole though: in your phone's Bluetooth settings, forget the MPPT entirely and re-pair from scratch. I had a similar nightmare with mine and it turned out the pairing had somehow got into a weird state. Sorted it completely without needing a firmware update.

What phone are you on? Android and iOS seem to behave quite differently with Victron's Bluetooth stack in my experience.

Mine dropped connection so many times I started wondering if Victron was ghosting me on purpose — turns out I had two phones both paired to it simultaneously, which apparently sends the Bluetooth stack into a proper strop; unpaired everything and started fresh and it's been solid since. Worth checking your paired devices list on the MPPT itself via VictronConnect settings before you go rebuilding the whole universe @Chopper62.

Really common one this, @Chopper62. Something nobody's mentioned yet — have a look at whether you've got Instant Readout enabled in the VictronConnect settings. On some firmware versions this can cause the Bluetooth stack to get itself in a knot during an active session, particularly if your phone's screen times out while connected. Try disabling it and see if your sessions stay stable.

Also worth checking if anything nearby is hammering the 2.4GHz band — a dodgy microwave or a crowded WiFi environment can cause more Bluetooth grief than people realise, especially in a confined space like a van or boat.

If none of that helps, a full PIN reset on the MPPT itself (hold the button sequence per the manual) can sometimes clear whatever's causing the handshake to fall over. Let us know how you get on!

Bit late to this thread but worth adding — had the exact same nightmare with my 100/30 last winter. Turned out the Bluetooth PIN had somehow reset and my phone was silently trying the wrong one in the background, causing it to hang rather than fail cleanly. VictronConnect doesn't always throw a useful error, just sits there then boots you out.

Go into VictronConnect settings, forget the device completely, then re-pair from scratch. Sounds obvious but the app sometimes holds onto a corrupted pairing state even across phone restarts.

Also — and this might be unrelated to your specific issue — older versions of Android have a known quirk where location permissions being set to "only while using" can interrupt BLE sessions. Worth checking that too alongside what @BatteryCol mentioned.

Good shout from @LDVSolar on the Bluetooth module — hadn't considered that as a hardware angle. Quick question though: has anyone found that the distance between phone and MPPT makes a meaningful difference here? I'm wondering whether being right next to the unit vs. a few metres away through a bulkhead changes the stability of the connection? My setup has the 100/30 mounted in a separate battery compartment and I'm always connecting through a thin ply panel. Could that be contributing to drops even after the software fixes people are suggesting?