question

Here is a pic of the manuals that came with my bus.

To upgrade my firmware, I connected to my Multiplus with the device below and then used VE Configure, which you can download from the Victron site. You need an RJ45 (ethernet style) cable to connect this device to the Multiplus.

If you are at all uncomfortable doing this, it might be best to find a Victron distributor and get help from someone who is knowledgeable about the equipment.

There is also a Bluetooth Dongle for the Multiplus that you can get, but I haven't used it.

I have the bluetooth dongle! I forgot to say that, sorry. Here is a pic. Can I update firware in this app?

I didn't mean for that image to be so huge. Can I update firmware using this app if I have the dongle?

I also just got a high temp alert, so not sure what's going on. Any help is appreciated.

You say the inverter is mounted under the bed. What provision has been made for ventilation?

Victron Connect should allow you to update the firmware on the Multiplus if you have the Bluetooth dongle, but I have not tried that. I found though that VE Configure was better than Victron Connect for adjusting the settings on the Multiplus. I don't remember the exact difference though.

Careful.

The MK3 USB interface pictured above is not Bluetooth. It's USB on the pc end. Other end uses fully wired Lan cable, but not the lan protocol.

Firmware update will delete all settings, so you need to make a note of them and reconfigure afterwards. You can also download/store the settings and upload after the firmware update, but I've never got it to work.

Low pitched hum is probably the transformer in the unit. Not likely that a firmware update will affect it.

Any chance of you just running off batteries overnight? Might be the easiest solution.

On the temp alert, yes check ventilation. Airflow is from bottom to top, usually convection is enough but the hot air needs to go somewhere and be replaced by cold.

@kevgermany I have been turning off the charger at night, but leaving it to invert, is that ok to do? I wake up to batteries at about 20% because I'm running a small dehumidifier.

I have wondered if there's enough ventilation under there. The builder put in a small vent to allow heat to escape into the rest of the under the bed area, but it's not connected to a fan to actually draw the heat out. That being said, the fan seldom came on throughout the hot summer, so I'm not sure why it's doing it now. I'm going to reach out to a Victron distributor this week to get some more advice. I think I'll wait to let someone more qualified update the firmware.

You mentioned settings. I haven't changed the settings on anything. I'm reading through posts here and I realize maybe I shouldn't be letting the batteries charge to 100% all the time. I think the battery life would be longer if I only allowed the batteries to charge to 80% or something? Do you have any thoughts about that? I have a lot to learn here. I worry I'm ruining my system and it would be horrifically expensive to replace so I'm trying to learn a lot very quickly.

If they're lead batteries, running down to 20% SOC will kill them quickly. And 100% SOC is best. If lithium, some people say don't overcharge, but LiFePo4 doesn't mind going to 100% and the BMS won't kick in to balance the cells until it's close to 100%. There's an awful lot of BS around. Lithium ion is a different case and the two chemistries are often mixed up.

Turning off at night clearly isn't an option.

Is the loud noise the fan on the multiplus? If it is, increasing ventilation should help.

Just wondering if it's summer or winter where you are. If it's summer, could easily explain the problem. And making sure there's an air inlet as well as exit to the compartment would be a good idea. Small pc fan may help.

@kevgermany This is the SKU from the batteries. Looks like they are lithium. chins-12300-211101-119. I'm suffering after the fact sticker shock, I had no idea what I'd paid for just one of those batteries.

I have never changed how much they are allowed to charge. They charge to 100% every day. I have only run them down below 50% a few times and that was all last week when I shut the solar off overnight. The only setting I have changed is switching it from 25-30A, depending on where I'm plugged into shore power. Right now I'm plugged into a 30A outlet. I have limited myself to these basic operations because I don't know WTF I'm doing and don't want to break it.

It is "winter" here in the PNW. It's been very cold for a month or so but now it's hovering around 45-50f during the day and staying well above freezing at night.

I'm including a photo that I hope makes clear the setup. The round black thing in the second picture is a vent he placed to siphon off heat,. He said it would let the heat out into the rest of the under the bed area, but it has no fan. I think overheating is the issue. I got a message in the app earlier that it was too hot under there. I will look into adding a small fan this weekend. What I don't understand is why it's just started doing this now, and not in the summer when it was so hot. Could it be because i'm running an electric heater and using kitchen appliances more? I don't know.

I THINK the loud noise is the fan on the multiplus, because when I switch off the charger and just leave the inverter on it stops.

*never mind about the pics, can't get them to upload, too tired to keep trying.