Ventilation for VE Multiplus II 24V 2x120

[sgprice]

Last year I did an install of a 24V battery bank (3 - LiTime 24V 230Ah LiFePO4’s, soon to be 4) and a VE Multiplus II 24V 2x120. I put everything behind the wall in the front bay/pass thru storage area (after getting everything off the floor and cleaning up the rats nest wiring job). I made sure there was good space below the inverter to draw in air and left space above and behind the top edge for air flow exit from the inverter. When I put the walls back in place I left space at the top and put a vent on the bottom of the wall directly in front of where the inverter is. Photos below.

I did have a couple of times in hot weather (90-100 degree days) where I got an overheat warning on L1 and once where it shut down from overheating.

I may put in a second inverter in parallel to be able to handle more loads when needed, but I’m concerned about the additional heat, let alone already having a heat issue with just one inverter.

Here’s my question: I was thinking about mounting a couple of high flow computer fans that would turn on at a certain temp. But where best to put them? - at the top of the inverter to pull air through? At the bottom to push air through? Or at the top of the wall to pull air through the vent at the bottom of the wall to cycle more air through the whole space behind the wall?

In hindsight I kind of wish I had mounted the one (and for future 2nd ) inverter in the front genset bay as I have seen where others have mounted fans on either side to pull air in and push out thru the side walls so that air enters and exits through the propane bays so you are actually exchanging out side air (vs just moving around inside the enclosed bay). I wanted to do this but as I needed to put my large battery bank in the heated space mentioned above, I was concerned about the longer cable runs to the bank from the inverter location. And before some folks suggest just opening both storage bay doors for air flow for my current install - I have since done that when weather allows. I’m looking for a solution for when the weather does not allow or it’s not appropriate to do so.


Cheers

 

[Riverbug]

Give the choice, I would say better to pull air through than push it in. Computer fans or other would be a good way to do it. You could make a "duct" out of cardboard, wood, metal, or whatever to push it out of that space an into another. In my travel trailer, I push the air down into the belly from the storage bay; where my equipment is. I also have a vent hole between the living area and storage bay so in summer I'm sucking conditioned air from the living space into the storage bay.

 

[sgprice]

Thanks, good suggestions

 

[JKellerJr]

Following. please update if you end up doing anything

So far I've not had an issue with the inverter overheating but it was a concern with the way I mounted mine

 

[sgprice]

Following. please update if you end up doing anything

So far I've not had an issue with the inverter overheating but it was a concern with the way I mounted mine

Will do. At present I’m going to follow Riverbug’s advice and try a couple of fans (thermostat controlled) and either building some duct work to pull air from the area above the Multiplus to the other side of the bay wall, or maybe try these -

CoolerGuys Flexible 4 Inch Vent Duct Tubing with 120mm or 92mm Fan End Caps

This is a great way to vent your airstream where you need it. This tubing is completely flexible for placement around and through intricate cabinet work or through computer case obstacles.

www.coolerguys.com

By the way - great job on the cut outs on the walls. Looks great. I want to redo mine at some point. Also want to put an electrical outlet on the wall like you did. Did you tie that into the line that feeds the plug for the vac?

 

[Rideblue51]

I virtually have the exact same set up with 12v, all mounted in the battery bay of my 5th wheel. The original vent hose that was installed because of the former lead acid batteries remains. My plan was to add a computer fan and connect it to that vent hose. My biggest draw is my A/C. Spent last summer NASCARing around the southeast. Gets pretty damn hot and humidity down there. In Darlington, we had to run it 24/7. Never had a heat issue but was kind of expecting it. I still plan to hook a fan up to the vent hose.

 

[georgiadawg]

Last year I did an install of a 24V battery bank (3 - LiTime 24V 230Ah LiFePO4’s, soon to be 4) and a VE Multiplus II 24V 2x120. I put everything behind the wall in the front bay/pass thru storage area (after getting everything off the floor and cleaning up the rats nest wiring job). I made sure there was good space below the inverter to draw in air and left space above and behind the top edge for air flow exit from the inverter. When I put the walls back in place I left space at the top and put a vent on the bottom of the wall directly in front of where the inverter is. Photos below.

I did have a couple of times in hot weather (90-100 degree days) where I got an overheat warning on L1 and once where it shut down from overheating.

I may put in a second inverter in parallel to be able to handle more loads when needed, but I’m concerned about the additional heat, let alone already having a heat issue with just one inverter.

Here’s my question: I was thinking about mounting a couple of high flow computer fans that would turn on at a certain temp. But where best to put them? - at the top of the inverter to pull air through? At the bottom to push air through? Or at the top of the wall to pull air through the vent at the bottom of the wall to cycle more air through the whole space behind the wall?

In hindsight I kind of wish I had mounted the one (and for future 2nd ) inverter in the front genset bay as I have seen where others have mounted fans on either side to pull air in and push out thru the side walls so that air enters and exits through the propane bays so you are actually exchanging out side air (vs just moving around inside the enclosed bay). I wanted to do this but as I needed to put my large battery bank in the heated space mentioned above, I was concerned about the longer cable runs to the bank from the inverter location. And before some folks suggest just opening both storage bay doors for air flow for my current install - I have since done that when weather allows. I’m looking for a solution for when the weather does not allow or it’s not appropriate to do so.


Cheers

Sorry, but I’m just now seeing your post.

I installed my system in the washer/dryer closet and was concerned about high temps.

To handle that, I installed an exhaust fan in the side wall of the coach. I have a temp sensor and I use one of the relays on my Cerbo GX to switch the fan on /off. It works flawlessly.

See picture attached.

 

[Benton Harbor]

Last year I did an install of a 24V battery bank (3 - LiTime 24V 230Ah LiFePO4’s, soon to be 4) and a VE Multiplus II 24V 2x120. I put everything behind the wall in the front bay/pass thru storage area (after getting everything off the floor and cleaning up the rats nest wiring job). I made sure there was good space below the inverter to draw in air and left space above and behind the top edge for air flow exit from the inverter. When I put the walls back in place I left space at the top and put a vent on the bottom of the wall directly in front of where the inverter is. Photos below.

I did have a couple of times in hot weather (90-100 degree days) where I got an overheat warning on L1 and once where it shut down from overheating.

I may put in a second inverter in parallel to be able to handle more loads when needed, but I’m concerned about the additional heat, let alone already having a heat issue with just one inverter.

Here’s my question: I was thinking about mounting a couple of high flow computer fans that would turn on at a certain temp. But where best to put them? - at the top of the inverter to pull air through? At the bottom to push air through? Or at the top of the wall to pull air through the vent at the bottom of the wall to cycle more air through the whole space behind the wall?

In hindsight I kind of wish I had mounted the one (and for future 2nd ) inverter in the front genset bay as I have seen where others have mounted fans on either side to pull air in and push out thru the side walls so that air enters and exits through the propane bays so you are actually exchanging out side air (vs just moving around inside the enclosed bay). I wanted to do this but as I needed to put my large battery bank in the heated space mentioned above, I was concerned about the longer cable runs to the bank from the inverter location. And before some folks suggest just opening both storage bay doors for air flow for my current install - I have since done that when weather allows. I’m looking for a solution for when the weather does not allow or it’s not appropriate to do so.


Cheers

Good Morning,
We had a similar challenge. ON our Reflection 303, I resolved it by adding a computer fan to the existing battery vent and then cutting another hole on the other side of the hatch and added an exhaust vent using a Valterra vent that matched the existing vent, some tubing and zip ties with computer fan. I wired the two fans to Relay 1 on the Victron Cerbo GX. I then programmed a temperature probe that came with the Multiplus II to start the fans at 91F and to stop the fans at 90F. So far so good...

Here is a video of how I wired my fans (I did not produce it, just used it).

I hope this is helpful.
Bob

 

[Lance Glogowsky]

Good Morning,
We had a similar challenge. ON our Reflection 303, I resolved it by adding a computer fan to the existing battery vent and then cutting another hole on the other side of the hatch and added an exhaust vent using a Valterra vent that matched the existing vent, some tubing and zip ties with computer fan. I wired the two fans to Relay 1 on the Victron Cerbo GX. I then programmed a temperature probe that came with the Multiplus II to start the fans at 91F and to stop the fans at 90F. So far so good...

Here is a video of how I wired my fans (I did not produce it, just used it).

I hope this is helpful.
Bob

Do you have the air blowing in from the outside in the hose or out?

 

[el Rojo]

I realize I'm late to the party, but what about replacing the wood/fabric wall with a metal screen one?

 

[Benton Harbor]

Do you have the air blowing in from the outside in the hose or out?

I used the existing battery vent and tube for an intake. I cut another similar hole on the other side of the compartment, installed another valterra battery vent and tube. I added fans to both the intake and exhaust tubes. The intake tube angles downward to blow air into the bottom of the compartment.. The exhaust tube is attached near the top of the MultiPlus sucking the hot air. The two fans are wired together to the the relay. Outside air comes into the compartment through one, and warm air gets blown out rough the other. So far, so good.

 

[Benton Harbor]

I realize I'm late to the party, but what about replacing the wood/fabric wall with a metal screen one?

Could.

In our case, there wasn’t enough airflow without the one OEM one air vent. Even with the second vent but without the fans, I’d get a high heat warning frequently in warm weather. I think because we camp in Florida and in other warm weather areas, and our MultiPlus generates lots of additional heat, the heat had nowhere to go.

 

[Lance Glogowsky]

I used the existing battery vent and tube for an intake. I cut another similar hole on the other side of the compartment, installed another valterra battery vent and tube. I added fans to both the intake and exhaust tubes. The intake tube angles downward to blow air into the bottom of the compartment.. The exhaust tube is attached near the top of the MultiPlus sucking the hot air. The two fans are wired together to the the relay. Outside air comes into the compartment through one, and warm air gets blown out rough the other. So far, so good.

Thanks for the information. Last year, I thought my multi +2 was getting awful hot even though the installer said that’s normal. I’ll feel more comfortable in adding another vent and a couple blowers to just circulate the air. Of course if it’s real hot outside at the time that probably won’t help things.

 

[el Rojo]

Our Victron Multi Plus is in the pass through right below the laundry chute. Mined hasn't gotten hot, but I check it when it's under heavy load. In my case I can just raise the lid to the laundry chute to give it more air. The install wasn't planned for venting, it was easier to install there. The pass troughs are awful small to work in.

 

[Benton Harbor]

Ours is a 2022 model Multiplus II. Evidently, the newer Multiplus IIs are much better at dissipating heat and quieter too.