Victron MultiPlus 3000 overheating

[SeaLevel]

We just left on what is supposed to be a 3+ month trip, and it is our first test of our newly installed solar/inverter/battery upgrade. This system was installed by Lew Farber, so it should have been done correctly.

The problem we are having is with the MultiPlus overheating. It is getting hot to the touch and intermittently shutting down. It was installed in one of the outside storage compartments under a twin bed, and based on what is happening, it seems like it needs better ventilation and shouldn't be in such an airtight compartment. I just removed two pieces from the shroud to see if that would help, but I am looking for other ideas. I don't really want to do something like install a fan since it would need to blow into the cabin and that would make it even harder to keep things cool on a hot day. Any ideas?

[daleyocum]

Mine is installed in the same place and runs fine in the sealed up compartment. I do open it if we are, for example, running the AC for hours but otherwise don’t worry about it The only difference is mine is installed vertically (but upside down.) Not sure if that matters. Victron’s engineers may have assumed the unit would have been installed vertically with heat flowing up over the components. not pooling at the top.

Mine is the Multiplus 3000.

Does it overheat only under heavy loads?

[Rocinante]

(Mod Hat On)

Ok, I'll ask a key question: assuming you spoke with Lewster about this, what did he suggest?

Feels like you might be jumping in here to air a concern without even trying to work it out first with Lew. I hope that's not what is happening.

In any case, please be mindful of the Community Rules as you work through this potential issue:

"Customer Disputes
This forum is not intended to be a mechanism for people to solely vent frustrations about services, products, vendors, or sales. Please settle your differences with the seller, provider, manufacturer, or dealer through other means but not through our community."

(Mod Hat Off)

[SeaLevel]

Originally Posted by Rocinante

Ok, I'll ask a key question: assuming you spoke with Lewster about this, what did he suggest?

Feels like you might be jumping in here to air a concern without even trying to work it out first with Lew. I hope that's not what is happening.

I spoke to Lew first of course. He wasn't sure, which is why I was asking. It can sometimes be hard to troubleshoot remotely.

[daleyocum]

Here’s how mine is installed

[Rocinante]

Ok, so as long as this is a call for help, and not a customer dispute, carry on.

Given I have the same inverter under the bed in our 27FB, I'd guess, as you have, that more ventilation is needed. Ours gets warm from time to time, though it has yet to shut itself down for being too hot.

The warmest it has gotten to date, we were using a combination of shore, solar, and battery power to air condition the trailer since we were on 15-amp service. Whenever the air conditioner shut down, the inverter would switch from inverting to bulk charging. It got pretty warm under the bed, but the system never did shut down. Once the sun finally set, and air conditioning demand declined, things under the bed cooled off again.

[SeaLevel]

Originally Posted by daleyocum

Does it overheat only under heavy loads?

Thanks for taking the time to respond. I now think that is the case. I did some troubleshooting and discovered that even though I was connected to shore power, there was a problem with the shore power, or the EMS, and the AC was being rejected by the MultiPlus. So, instead of passing the AC through, the inverter stayed on and it was working very hard to run the Air Conditioning. I turned off the breaker at the source and reset that and the EMS, and things are working correctly now.


I wasn't pointing fingers at anyone. As stated, the system is new and therefore I am still learning. I now know to be cognizant of whether or not the inverter goes off when connected to shore power. If it doesn't, there is a problem with the power coming in. I would never have tried to run the air conditioning for that long, on purpose off the batteries. Things are working now and the batteries are being recharged.

[Rocinante]

Awesome, that sounds very reasonable indeed. We have not had that problem, but I can confirm from the experience I noted above that inverting and running the AC, followed by bulk charging and then inverting again, generates a respectable amount of heat. It's amazing that we could pull that off at all. We continue to be ridiculously impressed by our Victron system, which was installed by AM Solar. It's so cool that by twiddling the input dial to 15 amps so we could use our cousin's shore power source without blowing a breaker, we were able to make it all work. We can literally driveway surf anywhere without any risk of abusing our host's generosity.

[SeaLevel]

Originally Posted by Rocinante

(Mod Hat On)

Ok, I'll ask a key question: assuming you spoke with Lewster about this, what did he suggest?

Feels like you might be jumping in here to air a concern without even trying to work it out first with Lew. I hope that's not what is happening.

In any case, please be mindful of the Community Rules as you work through this potential issue:

"Customer Disputes
This forum is not intended to be a mechanism for people to solely vent frustrations about services, products, vendors, or sales. Please settle your differences with the seller, provider, manufacturer, or dealer through other means but not through our community."

(Mod Hat Off)

It's responses like this that make me not want to ever ask for help. You completely made your own assumptions and read into this the wrong way. Chill out a little bit.

[daleyocum]

I’m an electrical engineer so I can’t help thinking about this stuff. Lew has done a ton of these so his real-world experience counts for a lot. From a purely theoretical standpoint you wouldn’t normally mount a relatively delicate electronics/microprocessor board over the top of a bunch of heat-producing macho components. Heat rises and all that.

The unit was probably designed to mount vertically so air could enter through one end, pass over the components, and be sucked out by the fan. Under heavy loads the heat from the transformers and power semiconductors will collect under the main board with it on it’s back. The fan MIGHT be able to still push it out but convection won’t be helping so it won’t be as efficient.

In practice does this matter? Don’t know. If Lew has installed bunch on their back then maybe not and the solution might lay elsewhere.

[daleyocum]

Originally Posted by SeaLevel

Thanks for taking the time to respond. I now think that is the case. I did some troubleshooting and discovered that even though I was connected to shore power, there was a problem with the shore power, or the EMS, and the AC was being rejected by the MultiPlus. So, instead of passing the AC through, the inverter stayed on and it was working very hard to run the Air Conditioning. I turned off the breaker at the source and reset that and the EMS, and things are working correctly now.


I wasn't pointing fingers at anyone. As stated, the system is new and therefore I am still learning. I now know to be cognizant of whether or not the inverter goes off when connected to shore power. If it doesn't, there is a problem with the power coming in. I would never have tried to run the air conditioning for that long, on purpose off the batteries. Things are working now and the batteries are being recharged.

When we have AC on, the Multiplus is in the loop even when plugged into shore power. I wasn’t aware it would ever disconnect. If I set the unit to take, say, 30A from the shore power I’m pretty sure it is still doing it’s magic and inverting it and charging batteries.

[SeaLevel]

Originally Posted by daleyocum

In practice does this matter? Don’t know. If Lew has installed bunch on their back then maybe not and the solution might lay elsewhere.

Lew said that he has installed a lot of them this way, and hasn't encountered this problem. Now I'm not sure what is going on. I just ran it for a while on charger mode only, and it still got real hot and shutdown. When it shuts down it trips some extra breakers that were installed inside under the bed. I am trying it again on charger only with the door to the storage compartment open. I obviously can't count on that as the solution.


I think I can rule out the MultiPlus itself as the problem, because Lew and I already swapped out the original after an initial test before this trip where the same kind of thing happened.

[SeaLevel]

Originally Posted by daleyocum

When we have AC on, the Multiplus is in the loop even when plugged into shore power. I wasn’t aware it would ever disconnect. If I set the unit to take, say, 30A from the shore power I’m pretty sure it is still doing it’s magic and inverting it and charging batteries.

According to my manual, when you switch it to inverter on, if it senses AC on the AC in connection it will pass that through to the AC out connection, and the inverter on LED will go out. The mains on LED goes on, and the appropriate charger LED too, depending on if the batteries needs bulk, absorption or float. And that is what I see on the remote display.

[daleyocum]

Originally Posted by SeaLevel

Lew said that he has installed a lot of them this way, and hasn't encountered this problem. Now I'm not sure what is going on. I just ran it for a while on charger mode only, and it still got real hot and shutdown. When it shuts down it trips some extra breakers that were installed inside under the bed. I am trying it again on charger only with the door to the storage compartment open. I obviously can't count on that as the solution.


I think I can rule out the MultiPlus itself as the problem, because Lew and I already swapped out the original after an initial test before this trip where the same kind of thing happened.

Were the batteries discharged such that the Multiplus was producing a lot of current to charge them? If so if it could still be producing a significant amount of heat internally.

Is it doable to unbolt it and try flipping it on either end temporarily to see if that fixes the issue?

Another idea. Is it really hot in the compartment when it’s running? Anything over 150F is certainly too hot.

[daleyocum]

Originally Posted by SeaLevel

According to my manual, when you switch it to inverter on, if it senses AC on the AC in connection it will pass that through to the AC out connection, and the inverter on LED will go out. The mains on LED goes on, and the appropriate charger LED too, depending on if the batteries needs bulk, absorption or float. And that is what I see on the remote display.

That wouldn’t make sense in my application since I use it to boost the capacity of my little 2000w Honda generator to run the AC, etc. Maybe that was a setting I changed. It would defeat the purpose of a hybrid inverter unless it flips itself on and off instantly as the load changes.

[SeaLevel]

Originally Posted by daleyocum

That wouldn’t make sense in my application since I use it to boost the capacity of my little 2000w Honda generator to run the AC, etc. Maybe that was a setting I changed. It would defeat the purpose of a hybrid inverter unless it flips itself on and off instantly as the load changes.

I believe the PowerAssist feature would do just that - provide extra current on demand. The manual states: "... the MultiPlus will make sure that insufficient shore or generator power is immediately compensated for by power from the battery."

[daleyocum]

Originally Posted by SeaLevel

I believe the PowerAssist feature would do just that - provide extra current on demand. The manual states: "... the MultiPlus will make sure that insufficient shore or generator power is immediately compensated for by power from the battery."

Fancy! I’ll have to watch next time.

[SeaLevel]

Originally Posted by daleyocum

Were the batteries discharged such that the Multiplus was producing a lot of current to charge them? If so if it could still be producing a significant amount of heat internally.

Is it doable to unbolt it and try flipping it on either end temporarily to see if that fixes the issue?

Another idea. Is it really hot in the compartment when it’s running? Anything over 150F is certainly too hot.

The batteries were completely discharged, so yes, it was working hard to recharge them. It's dark out now, but a quick measurement leads me to believe it may be possible to flip it to vertical. I will discuss with Lew before doing that. It gets really hot in the compartment, as you can imagine a heat producing device like that would when running inside a mostly sealed up box.

[ghaynes755]

The manual says the vertical is preferred but horizontal is ok. But I'd hazard a guess that they may mean horizontal with what you have as the bottom mounted to a vertical wall.

I had a similar issue with another brand in a similar compartment. In summer time I had made a screen door that I could insert into the compartment door opening for additional airflow.

[daleyocum]

Originally Posted by SeaLevel

The batteries were completely discharged, so yes, it was working hard to recharge them. It's dark out now, but a quick measurement leads me to believe it may be possible to flip it to vertical. I will discuss with Lew before doing that. It gets really hot in the compartment, as you can imagine a heat producing device like that would when running inside a mostly sealed up box.

When you say it shuts down, is it an external breaker that’s tripping or the Multiplus itself? Breakers are thermal devices, of course, so if the ambient air is hot, they’ll trip much sooner.

My Multiplus has never complained but I must admit I’ve never checked how hot it gets when it’s really cranking. Maybe the immediate problem isn’t the Multiplus but its proximity to a breaker. My breakers aren’t mounted in the same compartment as the Multiplus.

If it IS getting up into the top end of the Muliplus’ temperature range (150F) then it sounds like a vent fan is still going to be in order. You might consider having a little exhaust fan to move the air into the hot water heater compartment next door.