Adding a Mr. Cool 18k mini split

[WillieRides57]

Just throwing this out for the smart guys on this forum. We went full autonomous in November with 3800 watts of solar, a 6000xp inverter and 2 x 100 ah Hiness Hi-5 LiOn batteries. Question: Would I be able to run a Mr. Cool 18k mini-split for AC on the current components or would I need to parallel a 2nd inverter. This will only be for cooling as I have radiant propane heaters for fall/winter seasons.

 

[JonMez]

Just throwing this out for the smart guys on this forum. We went full autonomous in November with 3800 watts of solar, a 6000xp inverter and 2 x 100 ah Hiness Hi-5 LiOn batteries. Question: Would I be able to run a Mr. Cool 18k mini-split for AC on the current components or would I need to parallel a 2nd inverter. This will only be for cooling as I have radiant propane heaters for fall/winter seasons.

No idea if you have enough batteries or solar but if you aren’t exceeding the 6000w output you should be fine with the one unit. 18,000 btu should be ~2000w maybe?

 

[WillieRides57]

I appreciate your comment. We will more-than-likely be moving forward on this, being conservative on usage here in Northern Arizona.

 

[doing it different]

If its inverter compressor they do not surge at all. They ramp the compressor quite gently

 

[chamilun]

Very little surgery. Usually run below 1000 watts but will ramp to 1800 especially in heat mode

 

[chrisski]

It will run it, but you’ll have to watch your loads, and plan for battery for those hot AZ nights.

You may also be a little short on panels for summertime 24 hour AC.

Although 1000 watts to 1800 watts is something your inverter can handle, there will need to be limits that guests / family often misunderstands or ignores.

A 1700 watt water boiler, the 1400 watt toaster, a 1500 watt iron, and that AC on may push you past your limits. Add one more item and it will.

Without a good energy audit, I’d budget 20 kWh of batteries just for the AC. Even in Flagstaff, the hot summer nights can be AC running 10 hours straight through the night with no sunshine.

I am in the AZ lowland desert and just today finished a 24 k BTU EG4 AC install, just to cool the batteries for my solar in my garage.

 

[WillieRides57]

We could add another 6 x 400 watt panels. Perhaps that might be the way to go. We don’t generally use many kWh but for washing clothes in the middle of the day. Propane heat, range, water heater, and dryer (I’m in the business) help lower electrical demand.

I probably need one more 100 aH LiOn battery for this. I never thought about the need to cool batteries, we only worry about keeping them warm in the winter.

 

[chrisski]

We could add another 6 x 400 watt panels. Perhaps that might be the way to go. We don’t generally use many kWh but for washing clothes in the middle of the day. Propane heat, range, water heater, and dryer (I’m in the business) help lower electrical demand.

I probably need one more 100 aH LiOn battery for this. I never thought about the need to cool batteries, we only worry about keeping them warm in the winter.

For cooling the batteries, you might not need it in Northern AZ. My lithium garage batteries reached 120 f last year. I need it for that. Northern AZ is 20 degrees cooler give or take the adjustment for altitude.

Have you done a power audit and added the consumption for the new AC? I’d be curious for the results.

 

[WillieRides57]

Yeah, that is very warm. I’ve worked in attics at 130+ and can understand the issue.

I did an audit years ago but not recently. We started with 208 watts of solar and an old 2424 inverter made by Xantrex predecessor (original property owner). Can you give me a run down of how to calculate an accurate one?

 

[chrisski]

I'd start with the kWh used daily. You may be able to get monthly kWh off an electric bill.

What is hard is high wattage items that are hardwired to the house like regular ACs and mini splits. There's a buit of guesswork involved. What you got in post#8 is much better data than I had before I installed mine.

System Energy Audit and Sizing Spread Sheet

Apr 20, 2020

Tool for estimating power usage and estimating system size

• FilterGuy
• Planning and Sizing Tools

 

[chamilun]

Ininstalled a 220 mini split for all the reasons above. They are definitely more efficient

 

[HardYakka]

Just throwing this out for the smart guys on this forum. We went full autonomous in November with 3800 watts of solar, a 6000xp inverter and 2 x 100 ah Hiness Hi-5 LiOn batteries. Question: Would I be able to run a Mr. Cool 18k mini-split for AC on the current components or would I need to parallel a 2nd inverter. This will only be for cooling as I have radiant propane heaters for fall/winter seasons.

Our 24K Mr. Cool has been working flawlessly, summer and winter for 5 yrs going on 6th season. Very low surge, consumption and noise.
Put 3 Pioneer heads with 48kw inverter in new house, 12kw x 2 and 24kw, 1 XP ran them fine at 84%-ish capacity, but replacing EG4 with new old stuff (4448PAEx2).

 

[WillieRides57]

I'd start with the kWh used daily. You may be able to get monthly kWh off an electric bill.

What is hard is high wattage items that are hardwired to the house like regular ACs and mini splits. There's a buit of guesswork involved. What you got in post#8 is much better data than I had before I installed mine.

System Energy Audit and Sizing Spread Sheet

Apr 20, 2020

Tool for estimating power usage and estimating system size

• FilterGuy
• Planning and Sizing Tools

We are totally off-grid, so no access to a comparable values.

I will try the attached calculation spreadsheet to see where we are. Very blessed to really not have any high wattage appliances other than the washing machine.

Thank you for your insight.

 

[Koyaanisqatsi]

I have a Fujitsu 18K BTU mini-split in our upstairs bedroom. It's on a 20A breaker, and it's electrical load tops out at about 9A, or about 2160W. It's almost never running that hard, even in +100F weather. It only peaks there once in a great while, when I crank it cold (or hot in the winter) And it's in our upstairs, which gets REALLY hot in the summer time. The unit runs almost continuously throughout July and August.

 

[WillieRides57]

I have a Fujitsu 18K BTU mini-split in our upstairs bedroom. It's on a 20A breaker, and it's electrical load tops out at about 9A, or about 2160W. It's almost never running that hard, even in +100F weather. It only peaks there once in a great while, when I crank it cold (or hot in the winter) And it's in our upstairs, which gets REALLY hot in the summer time. The unit runs almost continuously throughout July and August.

View attachment 289149

Thanks for sharing your experience. I am beginning to understand that my system as-is may work just fine.

 

[chrisski]

On a side note, in Northern AZ, have you ever stopped into NAZ solar at Flagstaff and looked at their showroom?

Supposed to be another store in the Kingman area that sells solar over the shelf.

The only solar I see locally in the Phoenix valley is way too way overpriced compared to Amazon. Locally, it’sRV dealers and hardware stores.

 

[WillieRides57]

Yes, I have purchased from them over the years.

 

[Brett V]

I have a 24,000 BTU mini split that ran fine on a 6k Growatt. As was mentioned, you have to be conscious about your loads, depending on what else is in the house. I eventually upgraded to a 12k Growatt because I could never get the warden to remember that she couldn’t turn up the AC while the microwave and toaster oven were on and while she used the hairdryer.

 

[onokai]

I run two 18k mr cools for cooling but my whole system is larger and we have other loads and 22.5kw in battery storage at night.Our panels are 24 ,400 watt panels 5 years old now 9,6oo watts on paper but never seen taht much in extreme Nor-cal.We live near coast so cooling is radom use but did use them for heating most of winter (we have two other heat sources as well). I tghink you will need to pay close attention to your other loads. The mr cools just sip watts and really are not a surge and works best on for longer periods -they are better for cooling than heating to some degree (no pun intended)

 

[Lprantner]

It will run it, but you’ll have to watch your loads, and plan for battery for those hot AZ nights.

You may also be a little short on panels for summertime 24 hour AC.

Although 1000 watts to 1800 watts is something your inverter can handle, there will need to be limits that guests / family often misunderstands or ignores.

A 1700 watt water boiler, the 1400 watt toaster, a 1500 watt iron, and that AC on may push you past your limits. Add one more item and it will.

Without a good energy audit, I’d budget 20 kWh of batteries just for the AC. Even in Flagstaff, the hot summer nights can be AC running 10 hours straight through the night with no sunshine.

I am in the AZ lowland desert and just today finished a 24 k BTU EG4 AC install, just to cool the batteries for my solar in my garage

 

[Lprantner]

The 6000xp is limited to 3000w PER LEG on 240vac as a reminder. It will shut down if you exceed 3kw on EITHER leg.