diy solar

diy solar

YES: RV Solar/ Li/ and AC running full time

Generis

It'll be fun they said
Joined
Aug 21, 2020
Messages
84
Location
Ontario Canada
Hi, Everyone! I have been RVing for some years, and Solar powered stuff for some years, and Lithium powered for at least 15 years... and just finally got tired of all the people who complaining you CAN'T do your RV solar to run AC full time. Just drives me crazy. As you all know it's just math... Load, storage, and recovery. The truth is YES YOU CAN.

ANYWAY... I've been running this system full time for 2 years and it's so dead reliable that I finally decided to post up a video of the thing here:

As well, if you're wondering about the stuff I used in this build, I have most of it on a list I made on Amazon (they happen to have most of the stuff) so that's linked here: NOT AFFILIATE at all: www.amazon.ca/hz/wishlist/ls/33APLE6CUFI9E

And I'll describe the build here below in this list:
Batteries: Valence u27xp-12 and there's 4 of them currently, total ~7000wh storage.
Solar: 3x 72 cell ~395w panels, Just over 1kw solar on the roof, average ~800w laid flat and my latitude.
Charger: EPever 60a Mppt. runs amazing. (Also had a 40a that was amazing.)
AC unit: Senville 9000btu split AC/Heatpump... although the list shows the 220v version, I have the 110v version
Invertor: Renogy 2000w 12v, solid performer.

Obviously there's cables, fuses, and other stuff that's added... I can't stress enough how important the cable connections are.. they have to be just crazy good to eliminate heat and create resistive problems in your efficiency.. the Renogy comes with cables, which happen to be great, and that's the highest load on the system. The charger to battery bank, and then battery to battery is also super important.
Anyway, I'm happy to answer any questions you might have.. just wanted to show you all that this is TOTALLY possible for not a hideous amount of money, and it's working great... tested for hundreds of hours, and all weather. It just plain works.
Cheers, happy trails!
 
How about some info about how you ran the refrigerant lines and power to the unit?

I see that unit is 208/230 ..... is all the AC in the coach the same?
 
How about some info about how you ran the refrigerant lines and power to the unit?

I see that unit is 208/230 ..... is all the AC in the coach the same?
Sure, I think this will let me add pics.. I'll do that in a minute.
As stated in my thread list, the unit I could find to link was a 208 unit, although I do have the 110v version. My inside house electrical as you know is also 110.
 
As stated in my thread list, the unit I could find to link was a 208 unit, although I do have the 110v version. My inside house electrical as you know is also 110.
Sorry ... missed that ... just looked at the link.
 
Thanks for the info! My specs will be similar to yours in my 24 foot self built skoolie. I will have one more solar panel and 10kwhr battery bank. This is encouraging ?
 
Your install is much what I am planing. Rear mount , lines running forward to above the entry door.
So you followed the frame rail up and over the axle to go forward? Have you had any problems by causing a “trap” in the line set?

Very encouraging that you are getting reliable performance out of your system

Thanks for posting
 
Your install is much what I am planing. Rear mount , lines running forward to above the entry door.
So you followed the frame rail up and over the axle to go forward? Have you had any problems by causing a “trap” in the line set?

Very encouraging that you are getting reliable performance out of your system

Thanks for posting
Thanks for the comments, we are truly happy with this system.
I believe in a setup of pumped pressure you can't have a trap... It's pressure and not flow that causes these to work at all, and piping route has no affect on pressure. In any case there's no issues at all!
 
One other question,.
You seem to have it mounted very close to your back wall. Most of these units call for a much greater space.

Any problems there?
Interesting question. No problem. My rear wall does taper.. it's around an inch of space on top of the unit and closer to 3 inches at the bottom.
Also keep in mind the coil outside has a large rear AND side vent, so the innermost side is completely open, no resistance at all. And the fan runs so slowly there's no way the air is restricted at all.

These units do NOT have any start up surge. I'll explain it below:

While the AC is running, a general cycle looks like this:
Interior fan set to auto. It's always blowing some small amount of air to circulate.
It decides to cool. Outdoor fan comes on. Like pedalling a bike. Slow turns, very slow, and then slight increase in speed. It uses maybe 50 watts.
Then the compressor comes on. Really slow, same sort of ramp up style. Rolling along up to usually 750w, as it ramps, and the fan slowly beginning to ramp up with it.
The unit runs at 750w power for maybe 2 minutes or less, then slowly ramps down to 550w, a couple more minutes, then down to 450, then 400, and it will hold that for several minutes to do it's actual cooling cycle, until it decides to shut off based on your heat load.
Same slow ramp down to off.
There's never a surge ever. It's always slow transition. Basically perfect for low power consumption, and solar setups.

Other data: on "turbo" mode you can use it to hang meat in a cooler. It's just about ice coming out. But it will also consume 900+ watts... And on any heat mode (not efficient) it will ramp to a terrific 950w and hold that for extended periods of time. Not efficient for heating, although it's a very nice heater!

I believe the key for these systems to be efficient over time is to leave them on. After initial cool down, they consume very little as maintenance.
Cheers
 
I’d always thought that the inside unit on the mini split had to be mounted so that it stuck through the wall. Appears that was not the case. Not cutting through the wall and worrying about cutting the frame makes the installation much easier than I thought.

90 degree outside temps and 72 degree inside temps with less than 40 amps 12 volts draw on the batteries is pretty decent.
 
I’d always thought that the inside unit on the mini split had to be mounted so that it stuck through the wall. Appears that was not the case. Not cutting through the wall and worrying about cutting the frame makes the installation much easier than I thought.

90 degree outside temps and 72 degree inside temps is pretty decent.
I was also happy to see there were several line options at the head unit. Right or left, side or down or behind. Install wasn't as bad as I'd expected.

Considering the cooldown-for-consumption ratio I'm getting, it's no where near maxed out. For more power use I could handle way more heat outside or way cooler inside. Lots of room there.
 
Considering the cooldown-for-consumption ratio I'm getting, it's no where near maxed out. For more power use I could handle way more heat outside or way cooler inside. Lots of room there.
I think I’d need two of those units for my 35’ RV. I don’t see the wall space for them without taking the kitchen cabinets down or placing them on a slide out, which because of piping I don’t think would work. You got me thinking about it though.
 
I think I’d need two of those units for my 35’ RV. I don’t see the wall space for them without taking the kitchen cabinets down or placing them on a slide out, which because of piping I don’t think would work. You got me thinking about it though.
I have a couple of suggestions... with an extra 10 feet of roof (over my size 24') you could likely get 2k worth of solar, and then bump up to the 12000 size unit without any struggle. The difference between the 9000 and the 12000 is obviously an additional 30% cooling.. which should nicely compensate for the size of the RV. I'll suggest you put the indoor unit in your most used living area to be realized the best benefit. I've seen people put them in the bedroom and hope the rest of the unit gets cooled down, and then it runs forever... due to poor placement. Something to consider.
Due to this working at my levels, you should be able to throw some basic math at it and make a system that will rival mine at any up-leveled size. I still believe it's worth it. I'll never do a trailer or RV without this sort of thing. (partly because I can't stand the noise and horrific typical roof AC units)
 
Thanks for the comments, we are truly happy with this system.
I believe in a setup of pumped pressure you can't have a trap... It's pressure and not flow that causes these to work at all, and piping route has no affect on pressure. In any case there's no issues at all!

Great info, thanks again.

My RV is 22', has decent insulation, dark tinted windows with double shades. Most of the roof is shaded with panels, 800 watts at the moment and will add another 250 watts and a second fan when the roof air goes away.

My battery system is a little smaller than yours, only 300 Ah of BattleBorn but I do have a 2000 Watt Zantrex that should run it. I will not get as much run time as you.

If it all performs (except for the run time) I will dump my generator and build a 24 volt 10Kwh battery with stand alone inverter for my A/C-AC needs.

Sigh, the things we do to keep our pets happy while we go fishing

I think this is going to work.

P.S. I'm looking at the Panasonic Pioneer 9K BTU 21.5 SEER unit

Edit: to change Panasonic to Pioneer
 
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Great info, thanks again.

My RV is 22', has decent insulation, dark tinted windows with double shades. Most of the roof is shaded with panels, 800 watts at the moment and will add another 250 watts and a second fan when the roof air goes away.

My battery system is a little smaller than yours, only 300 Ah of BattleBorn but I do have a 2000 Watt Zantrex that should run it. I will not get as much run time as you.

If it all performs (except for the run time) I will dump my generator and build a 24 volt 10Kwh battery with stand alone inverter for my A/C-AC needs.

Sigh, the things we do to keep our pets happy while we go fishing

I think this is going to work.

P.S. I'm looking at the Panasonic 9K BTU 21.5 SEER unit
That all sounds great for sure! I've never consumed anything more than 150ah on any overnight, so the 300ah storage would be enough for my unit. I have way more, but it's never needed so far. Fortunately the AC on the roof is a large cumbersome thing that is also heavy, so getting it OFF saves weight and lots of space! Yay!
The panasonic 9k sounds great as well. I can only assume they are very similar in their design and operation, low wattage ramp controls etc.
I have no generator on board.. the unit we have did not come with one at all. I'm sortof wishing it did, because that would have been a great place for all the batteries as you say.
Hearts for fishing! haha
 
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