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Eg4 mini split and charging batteries

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AtomicPhil

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Ok so I want to start having an ac system and something I cannot get off my head. Is it possible to use solar panels to start the eg4 hybrid mini split and charge batteries at the same time instead of having a separate panel system? Just going to start buying parts here and there.

Thanks
 
AtomicPhil said:
Ok so I want to start having an ac system and something I cannot get off my head. Is it possible to use solar panels to start the eg4 hybrid mini split and charge batteries at the same time instead of having a separate panel system? Just going to start buying parts here and there.

Thanks
Click to expand...
No, it doesn't charge batteries. Or even use them.
It runs on the higher panel voltage.
 
Might work if you have a separate mppt charge controller. Whatever isn't used by the eg4 will go to the battery. Battery should discharge when mppt is not enough. You will be trusting bms to protect battery from over discharge.
 
And before you ask.
No, you can't connect the solar array to both at the same time. The two MPPT's will fight each other over control over the solar panels.
 
DIYrich said:
Might work if you have a separate mppt charge controller. Whatever isn't used by the eg4 will go to the battery. Battery should discharge when mppt is not enough. You will be trusting bms to protect battery from over discharge.
Click to expand...
The EG4 mini split doesn't have a battery connection.
It runs directly from the output of its internal MPPT.
It could be possible to open it up and connect to that circuit. But you would have to figure out what voltage it is. And build a battery for that voltage.
 
What happens if you connect the battery to the mppt (solar) port?

I see it needs 90v on the mppt. Buck boost 48v to 100v?
 
DIYrich said:
What happens if you connect the battery to the mppt (solar) port?

I see it needs 90v on the mppt. Buck boost 48v to 100v?
Click to expand...
That could be doable. If the buck boost is large enough to handle the amperage of the mini split.
 
Or.... You could just size your solar system to run a "regular" minisplit, and call it a day.

To be frank, I find this whole "solar minisplit" concept a bit gimmicky. From what I'm reading on this forum, if you don't have those "solar" minisplits set up to run only on solar, with no AC connection, they constantly draw at least some AC. And some reports here say that if they are set up for solar only, they sometimes have a problem restarting once they stop. I guess I could see buying one if you already have your system sized to run everything other than a minisplit, and then later decide you want to add said minisplit and don't want to upsize your inverter, etc. But otherwise, why not just size the solar system to run a good minisplit (Mitsubishi, Fujitsu, MrCool, etc.) and never worry about the solar-AC integration of just the minisplit? I actually like the minisplit specs of the EG4 units everyone is abuzz about, but the "added" solar just seems gimmicky to me. I suspect I'm in the minority on this one, though, and am happy to be shown the error of my ways, so push back as you wish.
 
Don't forget my getting raided by the PoCo gestapo, and then when they find its a solar mini split can't even figure out how they should react.

It does work very well for what I wanted it to do, simple offset of HVAC. If you DONT HAVE a "system" can't do that :)
 
It's attractive to people without a system yet because it has low startup cost without batteries or getting into your main wiring.
 
These are perfect for a shed or outbuilding with no power or minimal power where you want to add some climate control.
 
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Our cabin is fully off grid, I’ll eat a bit of efficiency by just running a 120v mini split only while we’re there.

The 1000w of panels needed for an EG4 will keep the batteries fully charged and happy even while using a mini split.
 
My advice would be to buy the Eg4 AC/DC Hybrid Mini-Split.
its actually $200 bucks cheaper than the Grid power one. supply and demand I guess.
$1200 bucks for a 12000BTU or 1 Ton Unit.

You can just plug some cheap Panels right into it and you’re done.
if your talking about running it thru a Solar Battery system plan on spending an arm and a leg just to get A/C
because you will need a beefy system to be able to run a mini-split and charge batteries for what ever else you may be using.
 

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740GLE said:
Our cabin is fully off grid, I’ll eat a bit of efficiency by just running a 120v mini split only while we’re there.

The 1000w of panels needed for an EG4 will keep the batteries fully charged and happy even while using a mini split.
Click to expand...
You must have a magic cabin on only 1000watts minus 20% efficiency. Lol

or are you saying your using 1000watts of panels dedicated to the mini-split so it doesnt eat up your batteries?
 
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DIYrich said:
I agree. If you size the solar to run the mini split, you waste all the power when the mini split isn't running.

You still need power to run the mini split when the sun isn't shining.

Easier to install a solar/AIO/battery.
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Much better to waste Power than to waste Money ramping your system up for something that’s only needed 1/4 of the year. hopefully By the time the sun goes down your nice and chilled and don’t have the sun beating down on your house. Running the mini-split on just stabilizing the temp instead of forcing the temp down should be minimal grid power usage.

There couldn’t be anything easier than just plugging some panels in. IMHO
 
Sundog33 said:
Much better to waste Power than to waste Money ramping your system up for something that’s only needed 1/4 of the year. hopefully By the time the sun goes down your nice and chilled and don’t have the sun beating down on your house. Running the mini-split on just stabilizing the temp instead of forcing the temp down should be minimal grid power usage.

There couldn’t be anything easier than just plugging some panels in. IMHO
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Not really wasting power, just wasting potential (the panels don't make power unless it has somewhere to go). Otherwise, I agree. Air conditioning and heating are by far our biggest loads. There are only a couple of months in the year that we can get by without some sort of cooling or heating.
 
AtomicPhil said:
Ok so I want to start having an ac system and something I cannot get off my head. Is it possible to use solar panels to start the eg4 hybrid mini split and charge batteries at the same time instead of having a separate panel system? Just going to start buying parts here and there.

Thanks
Click to expand...
It is possible with an MPPT, install a "Y" connector from the array going to the mini split and the MPPT. I've experimented with that configuration and the "excess" PV power will go to the MPPT to charge the batteries. When I say excess, when the mini split is only using 800 watts for example and you have potentially 1200 from the array. I did notice even with my mini split at max(1100) watts, there is always a small amount wattage going to the MPPT providing a trickle charge. Why it does this I don't have a clue,
 
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