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Mini Split on Solar

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Oldbikes

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Joined
Feb 8, 2022
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Doesn't seem to be much data on Mini splits on campers and it is very difficult to calculate anything because of the nature of these units. Current use varies due to variable speed drives ambient temp etc.​

So here are the measurements I made today

I have 2 100Ah 12V AGM Deep Cycle Batterys attached to 4 190 watt panels on a 25 ft motor home. Finally hooked it up today and ran it for a couple of hours.​

Amp draw was between 7 and 10 amps DC at 12.6 volts, the voltage stayed fairly constant for the duration of the test.These batteries power a 2000 watt inverter this has no load attached to it other than the mini split .
I suspect someone a lot better at math than me will be able to project run time etc however for me just getting everything to work is a major accomplishment .
It was 80 degrees today and partly cloudy / mostly sunny. I have no idea how much the solar was adding to the batteries but I would imagine it was break even at best.

The mini split is a 9,000 btu unit and I am running it on the dry mode, This seemed to keep the camper comfortable so that is what we will use when dry camping.

I had some left over parts so I assembled a solar generator, this has 4ea 100 Ah batteries that were sourced used from a phone company, 1 ea 190 watt panel, a Pwm controller and a 2,000 /4,000 watt inverter that I doubt would be able to produce more than 750 watts continuous.
In the near future I will hook this up to my furnace and induction cooker in case of a power outage. I tried charging a small electric car with it and it did work for a short while however things started getting fairly warm so that was was about a 15 minute test.
 
Oldbikes said:

Doesn't seem to be much data on Mini splits on campers and it is very difficult to calculate anything because of the nature of these units. Current use varies due to variable speed drives ambient temp etc.​

So here are the measurements I made today

I have 2 100Ah 12V AGM Deep Cycle Batterys attached to 4 190 watt panels on a 25 ft motor home. Finally hooked it up today and ran it for a couple of hours.​

Amp draw was between 7 and 10 amps DC at 12.6 volts, the voltage stayed fairly constant for the duration of the test.These batteries power a 2000 watt inverter this has no load attached to it other than the mini split .
I suspect someone a lot better at math than me will be able to project run time etc however for me just getting everything to work is a major accomplishment .
It was 80 degrees today and partly cloudy / mostly sunny. I have no idea how much the solar was adding to the batteries but I would imagine it was break even at best.

The mini split is a 9,000 btu unit and I am running it on the dry mode, This seemed to keep the camper comfortable so that is what we will use when dry camping.

I had some left over parts so I assembled a solar generator, this has 4ea 100 Ah batteries that were sourced used from a phone company, 1 ea 190 watt panel, a Pwm controller and a 2,000 /4,000 watt inverter that I doubt would be able to produce more than 750 watts continuous.
In the near future I will hook this up to my furnace and induction cooker in case of a power outage. I tried charging a small electric car with it and it did work for a short while however things started getting fairly warm so that was was about a 15 minute test.
Click to expand...
At 10 amps you are using 126 watts from your battery at 12.6v. If you are getting 600 watts off your solar, you are doing well. One good hour of sun (600 watt hours) might give you 4 or 5 hours of run time on the AC unit. I would round down as there are losses all over the system. Your battery might last 10 hours at 10 amps without adding charge. That would be using it at 50% depth of discharge and assuming it was in great condition.
 
It is very difficult to estimate what your runtime will be. It depends on the seer rating of your mini split. The actual temperatures you are going to to be running it in. How well your camper is insulated. The efficiency of your solar system ect.
DThames has probably as good a guess as you are going to get. I have been doing research myself on mini splits and would love to get specific data concerning mini split power consumption. So far the best information I have found is YouTubers that have installed and used mini splits on their campers hardly scientific data but at least something to guess with. At present I can in peak sun run my rooftop ac unit and still put a few amps per hour into my batteries. From what I have gathered I think I would cut my power consumption in half if I used a 21seer mini split. A soft start is almost half way monetarily to the purchase of a mini split. We live in the north and generally don’t need ac but should we start camping in the south we would have trouble sleeping without it. So I am trying to figure out if a mini-split might be right for us. Our rooftop ac unit is 22 years old so It can’t run forever. Any hard data on power consumption at different temperature differences would be a great help.
 
12VoltInstalls said:
There are dozens of threads on minisplits

Is there a question in this?
Click to expand...
No question , Just trying to add a bit of useful information to the board. I see a lot of questions posted like this one. https://diysolarforum.com/threads/mini-split-a-c-power-consumption.36712/ that was the only reason for my post.

I went about the project backwards instead of calculating my needs I purchased a used solar system came up for sale that was on a camper, one of the panels had blown off on them so instead of a 1200 watt system I downsized the camper solar to 800 watts. These panels were 190 watts each.

Also updated the controller to a Mppt so I had a single panel leftover and a Pwm charge controller, after getting some good used batteries and a 2,000 /4,000 watt inverter we put together a stationary solar generator. My intentions were to use the Solar generator for power outages and charge an electric golf cart. The current draw for charging the golf cart was higher than anticipated so that is a try it and see type of situation.
 
I have a 9000 BTU Senville mini-split on a 7 x 14 cargo trailer -> camper trailer conversion - e.g. 98sq ft. The trailer is insulated all-around (including floor and tailgate) with 1" Silverboard = R5 and no windows. The mini-split has soft start and maxes out at 1100w.

It uses ~5kwh/24hrs to keep 75F/24C in the moderate range of 45F/7C low and 95F/35C high. The most extreme I've used it so far was 25F/-4C low overnight and power went up to 12-15kwh/24hrs.

My best advice is to INSULATE and it will reduce power. I had no idea when I did the conversion, but next time I'll do as much insulation as I can - 2" / R10 is better than R5 and I'd even think about trying for 8ft wide / R40! instead of 7ft wide. :)
 
OffGridInTheCity said:
I have a 9000 BTU Senville mini-split on a 7 x 14 cargo trailer -> camper trailer conversion - e.g. 98sq ft. The trailer is insulated all-around (including floor and tailgate) with 1" Silverboard = R5 and no windows. The mini-split has soft start and maxes out at 1100w.

It uses ~5kwh/24hrs to keep 75F/24C in the moderate range of 45F/7C low and 95F/35C high. The most extreme I've used it so far was 25F/-4C low overnight and power went up to 12-15kwh/24hrs.

My best advice is to INSULATE and it will reduce power. I had no idea when I did the conversion, but next time I'll do as much insulation as I can - 2" / R10 is better than R5 and I'd even think about trying for 8ft wide / R40! instead of 7ft wide. :)
Click to expand...
What is the seer rating of your mini split?
 
DThames said:
At 10 amps you are using 126 watts from your battery at 12.6v. If you are getting 600 watts off your solar, you are doing well. One good hour of sun (600 watt hours) might give you 4 or 5 hours of run time on the AC unit. I would round down as there are losses all over the system. Your battery might last 10 hours at 10 amps without adding charge. That would be using it at 50% depth of discharge and assuming it was in great condition.
Click to expand...
Thanks for doing the math part for me, The solar system has been running for 2 days now and keeping the batteries charged even though the weather is not ideal for solar generation, We only use the mini split when we are in the camper (getting it ready to use for the season) so our power consumption is low at the moment.
 
Last edited:
OffGridInTheCity said:
I'm using a Senville "SENL/09CD/110v" model - https://senville.com/9000-btu-mini-split-air-conditioner-senl-09cd/
  • 19 SEER (HE) High Efficiency Air Conditioner & Heater
And oh yes,
- it is whisper quiet - both internal head unit and outside condenser unit. You don't hear a thing.
- they make a similar unit (more expensive) that works in extreme cold.

View attachment 93037
Click to expand...
I have heard that the silence alone is worth the switch even without the increased efficiency.
 
Oldbikes said:

Doesn't seem to be much data on Mini splits on campers and it is very difficult to calculate anything because of the nature of these units. Current use varies due to variable speed drives ambient temp etc.​

So here are the measurements I made today

I have 2 100Ah 12V AGM Deep Cycle Batterys attached to 4 190 watt panels on a 25 ft motor home. Finally hooked it up today and ran it for a couple of hours.​

Amp draw was between 7 and 10 amps DC at 12.6 volts, the voltage stayed fairly constant for the duration of the test.These batteries power a 2000 watt inverter this has no load attached to it other than the mini split .
I suspect someone a lot better at math than me will be able to project run time etc however for me just getting everything to work is a major accomplishment .
It was 80 degrees today and partly cloudy / mostly sunny. I have no idea how much the solar was adding to the batteries but I would imagine it was break even at best.

The mini split is a 9,000 btu unit and I am running it on the dry mode, This seemed to keep the camper comfortable so that is what we will use when dry camping.

I had some left over parts so I assembled a solar generator, this has 4ea 100 Ah batteries that were sourced used from a phone company, 1 ea 190 watt panel, a Pwm controller and a 2,000 /4,000 watt inverter that I doubt would be able to produce more than 750 watts continuous.
In the near future I will hook this up to my furnace and induction cooker in case of a power outage. I tried charging a small electric car with it and it did work for a short while however things started getting fairly warm so that was was about a 15 minute test.
Click to expand...

A little confused, you are running your minisplit off a 12 volt battery supply / 110 volt inverter correct? At 7 to 10 amps correct, this seems about right as far as a mini split. Except the watts were not correct . 10 amps at 110 volts is 1100 watts? Not 10 amps at 12.6 volts= 126 watts .So you are consuming 1100 watts per hour + inverter draw per hour. So you have panels that could produce 760 watts per hour? Your batteries will not last very long even if your system is producing 760 watts. But since you will not be producing max watts at any given time, think about upgrading panels to maybe 400 watts each. That would give you a possible 1600 watts per hour but more like 1280 in actuality. A minisplit running on 760 watts will be very hard to do. Especially since you only have 2400 stand by watts of storage in your battery system. 2400 watts will only last appx 2.18 hours. That is if they were Lithium batteries but you have AGM so you can only use 50 percent of your charged batteries without hurting your batteries. So now you have only 1.09 hours of backup battery power. Scratching my head about this.
 
OffGridInTheCity said:
I'm using a Senville "SENL/09CD/110v" model - https://senville.com/9000-btu-mini-split-air-conditioner-senl-09cd/
  • 19 SEER (HE) High Efficiency Air Conditioner & Heater
And oh yes,
- it is whisper quiet - both internal head unit and outside condenser unit. You don't hear a thing.
- they make a similar unit (more expensive) that works in extreme cold.

View attachment 93037
Click to expand...


Have you shared details of your build somewhere? I would love to read about it. I just ordered a 18x7' cargo trailer and planning/buying parts for the build
 
bedpan said:
Have you shared details of your build somewhere? I would love to read about it. I just ordered a 18x7' cargo trailer and planning/buying parts for the build
Click to expand...
I didn't except a few DIY battery pics and MPP Solar setup. Took me a year to build - we drop the tailgate and built a framework that gives us a 6 x 6ft room off the back for a bed or a table - so we 'kind of' a 7 x 20 (7 x 14 trailer + 6 x 6 tailgate room)

Here's a few pics... We bought cabinets from Lowes and stained them. Has a full shower (32" pan) + dry-flush toilet in the shower.
1655170824382.png

Did a 14s88p - e.g. 260ah @ 48v - DIY battery with Batrium BMS. That's about 10kwh useable.
1655170885543.png

MPP Solar 3048LV (3000w inverter) - wish I'd done 6000w :)
1655171000550.png

MaxxFan and 1200w of panels on top
1655171056900.png

Generator (propane or gas) left and 2 x 30lb propane bottles cabinet (right) - vented to outside
1655171602345.png

32" show + dry flush toile. That Dumawall in the shower and around the kitchen contertop - https://www.amazon.com/Dumawall-Interlocking-Waterproof-Backsplash-Smoked/dp/B075G2YGZK/ref=sr_1_2
1655171390383.png

Tailgate Room - double thick tarp.
1655171335299.png
 

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I don’t need and can’t really use a cargo trailer camper conversion but I lust to build one from scratch.
 
OffGridInTheCity said:
I didn't except a few DIY battery pics and MPP Solar setup. Took me a year to build - we drop the tailgate and built a framework that gives us a 6 x 6ft room off the back for a bed or a table - so we 'kind of' a 7 x 20 (7 x 14 trailer + 6 x 6 tailgate room)

Here's a few pics... We bought cabinets from Lowes and stained them. Has a full shower (32" pan) + dry-flush toilet in the shower.


Did a 14s88p - e.g. 260ah @ 48v - DIY battery with Batrium BMS. That's about 10kwh useable.


MPP Solar 3048LV (3000w inverter) - wish I'd done 6000w :)


MaxxFan and 1200w of panels on top
View attachment 98519

Generator (propane or gas) left and 2 x 30lb propane bottles cabinet (right) - vented to outside


32" show + dry flush toile. That Dumawall in the shower and around the kitchen contertop - https://www.amazon.com/Dumawall-Interlocking-Waterproof-Backsplash-Smoked/dp/B075G2YGZK/ref=sr_1_2
View attachment 98522

Tailgate Room - double thick tarp.
Click to expand...
Much thanks for sharing!

Might be worth starting another thread but I have a few questions. I will throw them out here but feel free to bounce to a new thread if you want or PM me if you prefer. You can ignore me as well if thats your preference ;-)

Can you tell me a little more about you bathroom? Do you know what floor pan you used? I see seams, is it just more of the Dumawall product? What toilet did you go with? And... What size water tanks are you using? I assume just a fresh tank and grey with no black?

Solar wize.. Thats quite the battery bank you got there! What size panels are you running? How did you attach them?

If your good with it I have more questions I am sure :)

Again thanks kindly!
 
Anyone doing mini splits in a mobile application needs to really pay attention on their connections, make sure their flairs are perfect. I have seen the line sets blow off at 550psi when they are not secured and the flair on the soft copper fails.
 
I have this unit on the way:
www.highseer.com

Pioneer® Diamante Ultra 12,000 BTU 22 SEER Wi-Fi Ductless Mini-Split Inverter++ Air Conditioner Heat Pump Full Set with 16 Ft. Kit - 110/120V

Summary Ultra High Efficiency Diamante Ultra Ductless Mini Split Heat Pump System Cooling capacity: 12,000 BTU/H with 22 SEER/12.5 EER efficiency Heating capacity: 12,000 BTU/H with 10 HSPF/3.5 COP efficiency Voltage: 110/120V, 60Hz, 1Ph High Wall Mounted Air Conditioning & Heating System...
www.highseer.com www.highseer.com

Along with 2,600W~ of solar or so. My first battery will be 6,720Wh and I have a 3000W generator as a backup.

My first task will be to install an autostart for the generator so it can cycle on as needed, the second will be doubling the bank (13,440Wh)

They rate it at 690W.. so I should be able to run it for 5-6 hours with no solar input, accounting for other loads and inversion losses, 80% lithium SoC.

I *should* be able to run it in full sun just off solar, the doubling of the bank should get be through the night without the generator.

Long term I may triple or quad the bank. Just depends on my actual usage and how well it fares.

I have a diesel heater for very cold nights.
 
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