Help me Install 3 EG4 Mini Split Solar Heat Pumps

[MrM1]

And I'm pulling the vacuum. 1 unit down ... 2 to Go

 

[Plum Crazy Rob]

Nice, must be tempting to throw some panels on the ground and test

I hope that is the 4" lineset cover it was hard to stuff lines into the 3".

 

[MrM1]

Yes tempting

 

[MrM1]

Nice, must be tempting to throw some panels on the ground and test

I hope that is the 4" lineset cover it was hard to stuff lines into the 3".

Yeah AC power? It's not gonna happen soon enough.

The wife said, "lets throw some panels in the yard and power it up" ?

Gotta love that woman

 

[MrM1]

Any way, evac done on the 1st 24k. 410a released. (System is not on)

 

[MrM1]

Ok ... DC power

Can a typical non-fused fin style Air Conditioning 60 amp disconnect be use by each mini split as a DC PV disconnect at the outside units ?

Because it's 240v AC L1/L2 it would break both DC positive and negative, but I'd be concerned about arcing. I'd be between 190 & 340vdc, and about 11 amps. And yet, how is it really any different than plugging 2 MC4 connectors together in a series string

But once installed it'd like rarely if every get used.

It's hard to cough up $80+ per unit when it could cost as little as $14

 

[timselectric]

Ok ... DC power

Can a typical non-fused fin style Air Conditioning 60 amp disconnect be use by each mini split as a DC PV disconnect at the outside units ?

Because it's 240v AC L1/L2 it would break both DC positive and negative, but I'd be concerned about arcing. I'd be between 190 & 340vdc, and about 11 amps. And yet, how is it really any different than plugging 2 MC4 connectors together in a series string

But once installed it'd like rarely if every get used.

It's hard to cough up $80+ per unit when it could cost as little as $14

It's not rated for it, so it wouldn't pass an inspection.
But, I would have zero concerns with using it.

 

[MrM1]

@timselectric
Would this fall into the arena of code next to the outdoor units? Specs are right

DIHOOL Miniature Circuit Breaker with din Rail Enclosure,20 Amp Solar Disconnect Switch, Outdoor Uv-Proof Box for Solar Panels https://a.co/d/2G0hoFG

 

[MrM1]

Ok, here's a question for the brain trust.

I will have 3 of these EG4 solar mini splits. Each will have its own 4-7 panel array.

I plan to modify a 3 string Midnite Solar combiner box so that the 3 Breakers do not combine the PV positives and each positive breaker would work independently. Easy. Just remove the combiner bar.

But in this box the negative PV is shared.

Can the negative from each array be shared / common, and still go off in 3 various directions to each mini split?

There will then be + & - disconnects at each unit.

 

[Bluedog225]

I wonder if anyone knows how large an air gap can an arc at 340vdc and about 11 amps can sustain? That is, after the plug is pulled.

Shirley this is in a table some where.

It would suck to find out the hard way.

 

[MrM1]

I wonder if anyone knows how large an air gap can an arc at 340vdc and about 11 amps can sustain? That is, after the plug is pulled.

Shirley this is in a table some where.

It would suck to find out the hard way.

Yeah I've moved on from the fin disconnect idea to the DC breaker concept

https://www.amazon.com/dp/B0B5QYFCTT?ref_=cm_sw_r_apan_dp_8KS5FTFGK9H9YFBHR5MJ

 

[MrM1]

Except now I'm thinking I might put the ac and dc discount Breakers on opposite ends of the same waterproof din rail box. Would look cleaner

 

[timselectric]

@timselectric
Would this fall into the arena of code next to the outdoor units? Specs are right

DIHOOL Miniature Circuit Breaker with din Rail Enclosure,20 Amp Solar Disconnect Switch, Outdoor Uv-Proof Box for Solar Panels https://a.co/d/2G0hoFG

If UL listed.
Yes

 

[timselectric]

Ok, here's a question for the brain trust.

I will have 3 of these EG4 solar mini splits. Each will have its own 4-7 panel array.

I plan to modify a 3 string Midnite Solar combiner box so that the 3 Breakers do not combine the PV positives and each positive breaker would work independently. Easy. Just remove the combiner bar.

But in this box the negative PV is shared.

Can the negative from each array be shared / common, and still go off in 3 various directions to each mini split?

There will then be + & - disconnects at each unit.

It would work fine, until a problem occurred on two strings at the same time. (Highly unlikely, but always a possibility)

 

[timselectric]

I wonder if anyone knows how large an air gap can an arc at 340vdc and about 11 amps can sustain? That is, after the plug is pulled.

Shirley this is in a table some where.

It would suck to find out the hard way.

I wouldn't be concerned because you are breaking the circuit in two places simultaneously. (+ and - )

 

[shopman]

Dry nitrogen aids in removing moisture from the system as well as testing for leaks so don't skip that step. Check all fittings under pressure with a soap and water solution and look for leaks. This is the best way to find tiny leaks. Also, these are heat pumps so that kink in the line should be repaired to work correctly. ANY restriction to refrigerant flow in a heat pump is not advised. One other tip. These type of units have a propensity to leak from the flair fittings so I personally always remove them where possible and use brazed joints instead. Pull a thorough vacuum below 500 microns before releasing the charge.

 

[MrM1]

Dry nitrogen aids in removing moisture from the system as well as testing for leaks so don't skip that step. Check all fittings under pressure with a soap and water solution and look for leaks. This is the best way to find tiny leaks. Also, these are heat pumps so that kink in the line should be repaired to work correctly. ANY restriction to refrigerant flow in a heat pump is not advised. One other tip. These type of units have a propensity to leak from the flair fittings so I personally always remove them where possible and use brazed joints instead. Pull a thorough vacuum below 500 microns before releasing the charge.

Did it

 

[MrM1]

OK ... so the 2 Ton is up and running on 6 NEO 335 watt panels at about 250v dc.

BUT ... what is up with the APP ???? I try to down load it and it says it is NOT AVAILABLE for Android 11 systems ?? REALLY ??

 

[MrM1]

Is it the Solar Aircon App? Yeah I can get it via my Android 10 phone but not my 11

How do you change from C to F using the Remote?

 

[Plum Crazy Rob]

I have Android 13 so WTF. Works fine. Engineer 775 says something about this too.

C to F instructions on back of remote lol. Ask me how I know ?