Advice Requested on Cooling EG4 System

[jolondon]

Hi.

I am installing a 6kw System here in Costa Rica at an off grid location consisting of an EG4 6ooo XP inverter and four EG4-LLS 100 AH batteries. I am installing on my property on the Caribbean side of Costa Rica, which is hot and humid.

I have two questions:

1) The temperature in the bodega, which is 4x3.75x 2 meters, is approximately daytime 80-85 degrees with a humidity around 85% also. As you can see in this picture I had left space at the top for ventilation but now I realize that I should have sealed it. I understand that humidity not temperature is the real enemy of solar equipment (the equipment is rated up to 100 degrees or so). My question is I can seal the top of the bodega as is or would it be wiser to cut the bodega in half with an interior wall so I am dehumidifying a smaller amount of space. I understand that it will be less work for the humidifier to dehumidify a smaller space but I also wonder if a smaller space wouldn't heat up faster? I can't place an ac in there because of the energy draw (this is an off grid location). fyi I purchased a 2500 foot dehumidiifer.

2) I am looking to alternatives to ac such as using fans. It doesn't seem an exhaust fan would do any good as I would be briniging in humid air from the outside which is what I want to avoid. From online research I did it seems the best way to cool components with a fan is to use the fan to pull the hot air away from the component. What are thoughts about using a front exhaust fan like this that would pull the hot air away from the batteries/inverter? I It only draws 8 watts. With my flexible shelving I can easily fit one on top of each battery (either directly on top or on a shelf). A few guys who have this type of fan said that it keeps their computer servers cool. thoughts or is there a better way to cool equipment without ac?

Thanks in advance for any and all help.

 

[rogerheflin]

You might as well put in an small AC and/or AC with a deumidifer setting. All of the dehumidifiers are basically AC units that dump the hot air back into the room so they will also heat the room which you probably do not want. If you use fans you would want to exhaust the air coming out of the rio 6000xp (that is where the all hot air will be, the batteries should have very minimal heat) outside and pull in the cooler outside air. Any humidity is only a problem IF you have colder surfaces and the humidity is condensing on the device.

 

[TM48]

The 6000 btu mini-split A/c I bought for my insulated 8x10' solar hut runs on just over 200 watts most of the time. On start up it consumed about 650w but slowly dropped to 200. Now this is in a reasonably well insulated building with no windows. R13 walls and a R30 ceiling.

 

[k490]

I'm in Phoenix, AZ we hit 119F this summer my EG4-6000XP running near peak power is in a 2 car garage 400 SQ feet. I put a 12k BTU mini-split in it is more then enough to control the heat mounted it right above the inverter. I think I could have gotten away with 9000 BTU.

 

[robby]

Trying to cool the same size room in Arizona at 30% humidity is a whole different thing than cooling one in Costa Rica at 85% humidity. It will be somewhere around 2-3 times as much energy because the AC unit first has to remove a significant amount of the Humidity before it even starts to really cool the room.

This chart gives you a rough idea of the difference.
Keep in mind that the Startup might be at 85% but as the rooms humidity drops you may be at 40% on the chart.

If cooling really becomes an issue then yes I agree go with a small mini split and preferably an Inverter based AC model that throttles down power usage once the cabinet is cool.
Given what I see with that room size and open roof a smaller well insulated DIY cabinet type enclosure would be needed.
The one problem is that you need some separate temperature controller for monitoring the Temp in the cabinet and if by some chance the AC fails, the monitoring system needs to alert you and eventually stop the Inverter if the cabinet is getting hot.

I have built projects using Fans and Louver vents to keep cabinets cool. They are extremely reliable and powerful. The first one I used has been running for four years and has never had a single issue. The intake at the bottom with one louver inward and the exhaust near the top with another louver outward.
I used AC Infinity Fans and components for these projects. You might get away with just this and be able to skip the AC unit. These Fans are incredibly powerful in comparison to the ones on the Inverter, so it may just keep the Inverter temp within limits.
Fan
Controller
Louver

If money permits this could also be used in conjunction with the AC unit as a fail over system.
The controller would be programmed to only turn on the Fan should the Temperature exceeds the Maximum, which would indicate that the AC has failed for some reason.
In normal operation the Fan would be off and the Louvers would be closed so the AC cooling losses inside would be minimal.

 

[Offgrid Jungle]

I have mine running in my bodega over in Quepos. I’m helping two neighbors install theirs too. The inverter is always on so the humidity is lower inside the 6000xp. I bought IP65 rated batteries for all three jobs. That was my biggest concern.

I installed a ventilation fan that blows hot air out and have a ventilated door that pulls the outside air in. The movement of air through the room makes it very pleasant.You don’t need the controlled model since i run it at full speed and it only uses 40 watts.

 

[jolondon]

The 6000 btu mini-split A/c I bought for my insulated 8x10' solar hut runs on just over 200 watts most of the time. On start up it consumed about 650w but slowly dropped to 200. Now this is in a reasonably well insulated building with no windows. R13 walls and a R30 ceiling.

Awesome. What brand/model did you get? I haven't seen one with such low consumption.

 

[jolondon]

I have mine running in my bodega over in Quepos. I’m helping two neighbors install theirs too. The inverter is always on so the humidity is lower inside the 6000xp. I bought IP65 rated batteries for all three jobs. That was my biggest concern.

I installed a ventilation fan that blows hot air out and have a ventilated door that pulls the outside air in. The movement of air through the room makes it very pleasant.You don’t need the controlled model since i run it at full speed and it only uses 40 watts.

View attachment 252941

Thanks so much. I didn't see any batteries that were 100 ah and IP 65 so I went ahead and got the EG4 batteries. I see that they are rated at 55% humidity. What does the fan really accomplish? That was my plan but now that I will use a dehumidifer woulnd't an exhaust fan just bring moist air in? What do you mean by the inverter always on helping? How does the address humidity issue? Thanks.

 

[jolondon]

The 6000 btu mini-split A/c I bought for my insulated 8x10' solar hut runs on just over 200 watts most of the time. On start up it consumed about 650w but slowly dropped to 200. Now this is in a reasonably well insulated building with no windows. R13 walls and a R30 ceiling.

Thanks..what is the brand of this mini split?

 

[rogerheflin]

A decent small high efficiency mini-split model that is say set at 80F is not going to use that much power so long as you have decent insulation and decent sealing. The biggest cooling loss in a house is the windows. Really really good windows are at best R-4.

You cannot really determine anything from the manufacture rated consumption except what the max power used is. Rarely do 2 manufactures test things the same way, unless legally required to. For your given conditions your insulation, internal heat generation and sealing will determine that. You probably want to see what the inverter's BTU output rating is at full load and factor that in. Bigger is typically better so long as the given unit is fully variable.

And I am not sure the 55% relative humidity rating you found means anything useful, being rated at 55% would be unworkable so I have to believe the rating means nothing at all except that was their "test" conditions. Typical electronics are rated 5%-95% non-condensing and I just found it on the 6000xp and it says the expected 5%-95%. Electronics do not usually care about humidity and the 95% max is because over that you start getting condensation and water inside electronics in places that it should not be is never good.

 

[TM48]

This nothing special just a Cooper & Hunter 6000 btu. Keep in mind this is cooling a small (8x10) room that is while not super insulated it is well insulated. The unit most of the time is operating at the low end of it's range. $725.00 delivered.

 

[jolondon]

Trying to cool the same size room in Arizona at 30% humidity is a whole different thing than cooling one in Costa Rica at 85% humidity. It will be somewhere around 2-3 times as much energy because the AC unit first has to remove a significant amount of the Humidity before it even starts to really cool the room.

This chart gives you a rough idea of the difference.

If cooling really becomes an issue then yes I agree go with a small mini split and preferably an Inverter based AC model that throttles down power usage once the cabinet is cool.
Given what I see with that room a smaller well insulated DIY cabinet type enclosure would be needed.
The one problem is that you need some separate temperature controller for monitoring the Temp in the cabinet and if by some chance the AC fails, the monitoring system needs to alert you and eventually stop the Inverter if the cabinet is too hot.

I have also built projects using Fans and Louver vents to keep cabinets cool. They are extremely reliable and powerful. The first one I used has been running for four years and has never had a single issue. The intake at the bottom with one louver inward and the exhaust near the top with another louver outward.
I used AC Infinity Fans and components for these projects. You might get away with just this and be able to skip the AC unit. This Fan is incredibly powerful in comparison to the ones on the Inverter, so it may just keep the Inverter temp within limits.
Fan
Controller
Louver

If money permits this could also be used in conjunction with the AC unit as a fail over system.
The controller would be programmed to only turn on the Fan should the Temperature exceeds the Maximum, which would indicate that the AC has failed for some reason.
In normal operation the Fan would be off and the Louvers would be closed so the AC cooling losses inside would be minimal.

ok questions for you. The metal marking on the inverter 6000 xp says operating temp up to 113 and the batteries eg4 ll says tup to 122. Inverter manual says the same and the battery manual says nothing though it does say for storage should not be greater than 55% humidity. So do I really need to worry about temperature? My storage room (bodega) is in the shade so it won't get over 90 and the msot I have seen it is 85 degrees. what are the advantages of a small cabinet over my present room? My bodega is well withinthe limits of the dehumidifier...how would i dehumidify a small cabinet? Would a fan do that? Thanks for all your suggestions above..quite helpful. But again with an exhaust fan wouldn't I just be bring in more humid air which I understand is the real killer of electronic components in my area.

 

[jolondon]

A decent small high efficiency mini-split model that is say set at 80F is not going to use that much power so long as you have decent insulation and decent sealing. The biggest cooling loss in a house is the windows. Really really good windows are at best R-4.

You cannot really determine anything from the manufacture rated consumption except what the max power used is. Rarely do 2 manufactures test things the same way, unless legally required to. For your given conditions your insulation, internal heat generation and sealing will determine that. You probably want to see what the inverter's BTU output rating is at full load and factor that in. Bigger is typically better so long as the given unit is fully variable.

And I am not sure the 55% relative humidity rating you found means anything useful, being rated at 55% would be unworkable so I have to believe the rating means nothing at all except that was their "test" conditions. Typical electronics are rated 5%-95% non-condensing and I just found it on the 6000xp and it says the expected 5%-95%. Electronics do not usually care about humidity and the 95% max is because over that you start getting condensation and water inside electronics in places that it should not be is never good.

55% is what they said for the batteries in storage..good catch. so are you saying that 85% humidity will not be an issue for the batteries or inverter?

 

[rogerheflin]

Where do you see the storage not greater than 55% humidity? The truck shipping out of their facility in the summer WILL have greater than 55% humidity at least some of the time and unless their warehouse is air conditions the humidity will be above that part of the year, so I am not sure who would have thought that was a reasonable value to list. The only reason for 55% storage may be so the BOX it is in does not fall apart and/or the shipping material does not degrade.

I would probably seal the room as well as you can (to limit dust and dirt and as many bugs as you can--all bigger issues) and put a unit in but set it at to like 85 and some high humidity value maybe 60-70%. Make sure the BTU of the unit is say 2-3x the max BTU heat output of the 6000 unit.

 

[rogerheflin]

55% is what they said for the batteries in storage..good catch. so are you saying that 85% humidity will not be an issue for the batteries or inverte

They say 93% efficient so assuming 10% of output is heat that translates to 600w of heat which translates to 2000btu and since are cooling only to a much higher temp that the AC units rating was at 6000btu(or smaller) is fine or just about any 20+ seer fully variable speed/inverter unit should be fine.

 

[jolondon]

Where do you see the storage not greater than 55% humidity? The truck shipping out of their facility in the summer WILL have greater than 55% humidity at least some of the time and unless their warehouse is air conditions the humidity will be above that part of the year, so I am not sure who would have thought that was a reasonable value to list. The only reason for 55% storage may be so the BOX it is in does not fall apart and/or the shipping material does not degrade.

I would probably seal the room as well as you can (to limit dust and dirt and as many bugs as you can--all bigger issues) and put a unit in but set it at to like 85 and some high humidity value maybe 60-70%. Make sure the BTU of the unit is say 2-3x the max BTU heat output of the 6000 unit.

 

[jolondon]

View attachment 253083

If 70% is a good humidity level like you wrote than I assume my dehumidifier will be working less which shoudl decrease power consumption (I would think).

 

[jolondon]

I'm in Phoenix, AZ we hit 119F this summer my EG4-6000XP running near peak power is in a 2 car garage 400 SQ feet. I put a 12k BTU mini-split in it is more then enough to control the heat mounted it right above the inverter. I think I could have gotten away with 9000 BTU.

Thanks..what is the temperature now of the room or near the inverter?

 

[TM48]

Not k490 but mine runs at 79F.

 

[jolondon]

Not k490 but mine runs at 79F.

machine or the room?

 

[TM48]

The room always the machines sometimes. Typically at sunup the inverters report 79F. My minimum load is 150 to 300 watts. The inverters idle most of the night. They may hit 98-100 during the peak charge time around 10-10:30. On a sunny day my batteries are fully charged by 10:30 am.

 

[rogerheflin]

Where do you see the storage not greater than 55% humidity? The truck shipping out of their facility in the summer WILL have greater than 55% humidity at least some of the time and unless their warehouse is air conditions the humidity will be above that part of the year, so I am not sure who would have thought that was a reasonable value to list. The only reason for 55% storage may be so the BOX it is in does not fall apart and/or the shipping material does not degrade.

I would probably seal the room as well as you can (to limit dust and dirt--a bigger issue) and put a unit in but set it at to like 85 and some highish humidity value maybe 60-70%. Make sure the BTU of the unit is say 2-3x the max BTU heat output of the 6000 unit.

If 70% is a good humidity level like you wrote than I assume my dehumidifier will be working less which shoudl decrease power consumption (I would think).

The dehumidifer is a heater. All of its power becomes heat and if you seal up the room with (so the dehumidifer works) then the room will get significantly hotter than the outside temp and you will have a problem.

 

[robby]

ok questions for you. The metal marking on the inverter 6000 xp says operating temp up to 113 and the batteries eg4 ll says tup to 122. Inverter manual says the same and the battery manual says nothing though it does say for storage should not be greater than 55% humidity. So do I really need to worry about temperature?

Yes, because the hotter the Batteries are is the less life you will get out of them.
High humidity is just going to make it more difficult for the batteries and Inverter to keep themselves cool by dampening their ability to radiate the heat they generate into the air.

My storage room (bodega) is in the shade so it won't get over 90 and the msot I have seen it is 85 degrees. what are the advantages of a small cabinet over my present room?

The benefit is that you can used forced air ventilation and keep a lot of air moving over them. This will result in a cooler operating temperature while having control over dust and other problems.

My bodega is well within the limits of the dehumidifier...how would i dehumidify a small cabinet? Would a fan do that? Thanks for all your suggestions above..quite helpful.

You could put the Evaporator of a mini split AC inside the Cabinet and the compressor outside.
This would be the ideal setup but it would use a lot more power than a Fan.

But again with an exhaust fan wouldn't I just be bring in more humid air which I understand is the real killer of electronic components in my area.

A fan won't increase the Humidity inside the cabinet.

Question, how much of that big room are you actually using for the Inverter and batteries.
I am assuming very little of it.

 

[rogerheflin]

Yes, because the hotter the Batteries are is the less life you will get out of them.
High humidity is just going to make it more difficult for the batteries and Inverter to keep themselves cool by dampening their ability to radiate the heat they generate into the air.


The benefit is that you can used forced air ventilation and keep a lot of air moving over them. This will result in a cooler operating temperature while having control over dust and other problems.

View attachment 253113


You could put the Evaporator of a mini split AC inside the Cabinet and the compressor outside.
This would be the ideal setup but it would use a lot more power than a Fan.

A fan won't increase the Humidity inside the cabinet.

Question, how much of that big room are you actually using for the Inverter and batteries.
I am assuming very little of it.

I forgot about the battery lifetime decreasing with heat, so setting it at 80 or less would be best. And ideal setup would be the AC unit having its intake be just about the Inverter and having the cold air blowing on the batteries. AC's get more efficient(energy to cooling capacity) the hotter the intake air is. computer rooms attempt to directly pull the hottest air in the room into the AC, and house AC do much the same (intakes high up).

Check the Seer rating on the unit, typically the slightly more expensive mini-splits are a lot more efficient than the window units and so use less power.

 

[jolondon]

Yes, because the hotter the Batteries are is the less life you will get out of them.
High humidity is just going to make it more difficult for the batteries and Inverter to keep themselves cool by dampening their ability to radiate the heat they generate into the air.


The benefit is that you can used forced air ventilation and keep a lot of air moving over them. This will result in a cooler operating temperature while having control over dust and other problems.

View attachment 253113


You could put the Evaporator of a mini split AC inside the Cabinet and the compressor outside.
This would be the ideal setup but it would use a lot more power than a Fan.

A fan won't increase the Humidity inside the cabinet.

Question, how much of that big room are you actually using for the Inverter and batteries.
I am assuming very little of it.

Here's the thing. You and others seem to be operating with the scenario in non tropical climates. You want your cabinet to be the same temperature as the surrounding room by taking away the machine heat. Makes senes. In my case if as in your drawing in air from surrounding the cabinet it will still be 86 degrees and 85% humidity - understanding that the air flow will help dissipate the air from the machine as you wrote.

In my situation first the EG4 batteries are of a non standard size..they don't fit a computer cabinet. Shipping the eg4 cabinet here seemed prohibiotive because it doesn't fold up and I would have had to pay an additional40% tax on it (solar equipment like inverters comes in tax free). EG4 support said some people just stack them on a table but that didn't sound wise to me. So I found a shelf that matches the width of the batteries perfectly (see this image). The inverter is wall mounted.

The space between the shelves and within shelves leaves good room for airflow.

I am thinking I could build a small closet basically over the rack with a door. Maybe use insulated panels or drywall. It would be basically sealed. And then place a dehumidifer in there (I bought one from Amazon that draws 230 watts). I can also put in a portable air conditioner and see how much power it draws. As someone else suggested, I can install one of those infinity fans that will take the air from the fans of the inverter and send it outside the enclosure.

What do you think of this idea? I am hoping that the relatively small space means that the dehumidifer and inverter would come in sporadically as the temperature/humidity rises or else I could put them on timers which is what some people do. this would keep down the power consumption.

Alternatively I could seal the top of the bodega and dehumidify or air condition the entire area. That would require a bigger ac unit/ dehumidiifer which would draw more power.

Thoughts?