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

I've had my 100/30 MPPT running since April on a fairly simple setup — two 200W panels in series feeding into a 200Ah lithium (a Fogstar Drift 12V). Everything's been brilliant until about three weeks ago when the Bluetooth started playing up. The controller is doing its job fine, charging away, but the VictronConnect app on my Android phone (Samsung S22, latest app version) just drops out every few minutes. Sometimes it won't even find the device at all on the initial scan.

I've tried the obvious stuff — restarting the app, forgetting and re-pairing the device, even doing a full PIN reset back to the default 000000. My phone is literally sitting 30cm away from the unit when I try to connect, so it's not a range issue. I did notice it started around the same time I updated the firmware on the SmartSolar to v3.14, so I'm wondering if that's introduced a bug, or whether I've just got a dodgy unit.

Has anyone else seen this on the 100/30 specifically, or on other Victron MPPT controllers? I'd rather not have to go through a warranty claim if there's a simple fix I've missed. Curious whether a firmware rollback is even possible and if so how you'd go about it.

Seen this exact thing on my shepherd's hut setup. Nine times out of ten it's the Bluetooth dropping rather than anything wrong with the MPPT itself.

Few things worth trying:

• Force close VictronConnect completely and reopen
• Check your phone's Bluetooth cache — Android especially gets grumpy with it
• Make sure VictronConnect is fully updated on your phone

Also worth checking if the 100/30 firmware needs updating — you can sometimes still connect long enough to push an update through before it drops again.

Mine did this repeatedly last summer, turned out my phone was the culprit. Swapped to an old tablet I keep in the hut purely for monitoring and haven't had a single dropout since.

@Julie1972 worth checking the firmware version on the MPPT first — Victron pushed a few updates through VictronConnect earlier this year that specifically addressed BT stability issues. Connect via USB-C OTG cable (or borrow a VE.Direct cable if you have one) rather than Bluetooth, then check under the device settings for available updates.

Also, if you're running the VictronConnect app on Android, there were some known handshake issues with certain Android 13/14 builds. iOS tends to be more reliable in my experience on the motorhome.

One other thing: sustained high ambient temperatures around the controller itself can occasionally cause the BT radio to throttle. Where's yours mounted? Mine's in a reasonably ventilated locker and I've had zero dropouts since ensuring proper airflow around the unit. Direct sun on the enclosure would be the first thing I'd rule out.

@Julie1972 I had something similar last summer with my 75/15. Worth checking whether it's specifically losing connection when the charge current is high — I found mine would drop Bluetooth intermittently during bulk charge on hot days. Turned out the unit was getting quite warm and it seemed to affect the radio. I repositioned it somewhere with better airflow and the dropouts largely stopped.

Also, have you got a phone case that might be blocking signal? Sounds daft but I swapped to holding my phone differently and it made a noticeable difference at range. The Bluetooth on these units isn't the strongest at the best of times.

As @Curly says, firmware is worth ruling out first though — definitely do that before anything else.

@Julie1972 one thing nobody's mentioned yet — have you got a GX device or a Raspberry Pi running VenusOS anywhere on the network? I found that when my setup tried to connect via two routes simultaneously (direct Bluetooth and through a local portal), the app got confused and dropped out repeatedly. Took me ages to pin down.

Also worth checking whether your phone's Bluetooth is being grabbed by something else nearby — smartwatches, speakers etc. can interfere more than you'd expect.

What firmware version are you currently on? The VictronConnect app itself also needs keeping up to date, not just the MPPT — I've been caught out by that before with my backup setup.

Hey @Julie1972, just to add to what the others have said — worth having a look at your phone's Bluetooth settings specifically. I had a very similar issue with my 100/20 and it turned out my Android phone was aggressively killing background Bluetooth connections to save battery. Once I whitelisted VictronConnect in the battery optimisation settings it was rock solid again. Also noticed that if you've got anything else paired nearby — a BT speaker, earbuds etc — sometimes there's a bit of interference causing dropouts. Try toggling Bluetooth off and back on before connecting and see if that helps narrow it down. Hopefully something simple like that rather than a firmware gremlin! Let us know what @Curly's firmware suggestion turns up first though, as that's probably the quickest thing to rule out. 👍

Funny you should mention this — my 100/30 on the shepherd's hut started playing up mid-July and it turned out the MPPT was just too warm inside the cabinet I'd mounted it in; once it throttles back due to heat, the Bluetooth seems to get a bit wobbly too. Worth sticking your hand near it and seeing if it's running hot.

Hey @Julie1972 — just to pick up where @FogstarGal left off, it's worth checking whether your MPPT firmware is current. Open VictronConnect when you do manage to connect and head straight to the settings cog — if there's an update available it'll flag it there. I had almost identical behaviour on my 75/15 last summer and a firmware update sorted it completely. Also worth noting that direct Bluetooth range is fairly limited, so if you're connecting from inside a building with the MPPT outside, walls can cause intermittent dropouts that look like something more serious than they actually are.