My 22MLE solar install of a modest system

**zygmunt** · 12-22-2021, 09:01 AM

I own a 2021 22 MLE and plan on going solar. I taking it one step at a time. I already have a lithium battery and plan to get another one before the project is complete. Due to supply chain issue, my RV been at the dealership for 3 months. The battery went dead and won't keep a charge. Instead on purchasing a new AGM battery, I would like to incorporate the lithium battery I already have and use it. I understand that the current battery charge on a 2021 22MLE will not charge a lithium battery to 100%, more like 80% which is fine until I complete the project. I also, would like to move the lithium indoors to underneath the queen size on the 22 MLE. How much work would it be to move the current battery cables for outside in the front to the inside under the bed?

If I already didn't have a lithium battery, I would just purchase a new AGM. The dealer charged the battery before I pick it up on last Tuesday, and by Thursday it was already dead. I brought home and hook it up a charger, and charged it to 100%. I brought the battery home again to keep it charged. I have a Victron IP65 12/15 charger and it stated it was already drain down to 50% after 3 hours usage at the RV.

Merry Christmas!

Thanks!

**zygmunt** · 12-22-2021, 12:18 PM

Hello Dan,
.
How easy was it to run the cables from the garage to the dinette area? How much cable did you use? Thanks!

Merry Christmas!

Zigman

**SailorDan** · 01-05-2022, 06:46 PM

Originally Posted by zygmunt

I own a 2021 22 MLE and plan on going solar. I taking it one step at a time. I already have a lithium battery and plan to get another one before the project is complete. Due to supply chain issue, my RV been at the dealership for 3 months. The battery went dead and won't keep a charge. Instead on purchasing a new AGM battery, I would like to incorporate the lithium battery I already have and use it. I understand that the current battery charge on a 2021 22MLE will not charge a lithium battery to 100%, more like 80% which is fine until I complete the project. I also, would like to move the lithium indoors to underneath the queen size on the 22 MLE. How much work would it be to move the current battery cables for outside in the front to the inside under the bed?

If I already didn't have a lithium battery, I would just purchase a new AGM. The dealer charged the battery before I pick it up on last Tuesday, and by Thursday it was already dead. I brought home and hook it up a charger, and charged it to 100%. I brought the battery home again to keep it charged. I have a Victron IP65 12/15 charger and it stated it was already drain down to 50% after 3 hours usage at the RV.

Merry Christmas!

Thanks!

Actually moving the battery and cable from the tongue to under the bed should not be too difficult. On the tongue if you follow the battery cables back along the passenger side (entrance door side) just behind the A frame is a metal box with cover. You can un bolt the existing cables there and run new ones up through the storage and then through the rear storage wall in the pass through to under the queen. You might think long term if you are going to add an inverter to get 110v when you have no shore power. The inverter should be located close to the batteries if possible, it needs a good size cable to supply the inverter from the batteries. That's mostly why I went for under the dinette where I could also tie into the 12v panel and put an automatic transfer switch on one of the breakers . It is right next to the wiring panel (both 12v and 110v). I have 350 watts of solar so I didn't need too big of wire to get from the solar charger wiring in the pass through to the 12V wiring back to the panel, I just used the existing wire in the solar prep. Plus if you think about it with the 12v battery on the tongue is running all the way back to the panel under the pantry as it is. It is crazy you drained the lithium that quick. How many AH is it? What could be running in the rig that is using that much battery? Is it cold there? A lithium cant charge below 32 degrees in most cases.

**SailorDan** · 01-05-2022, 06:54 PM

Originally Posted by zygmunt

Hello Dan,
.
How easy was it to run the cables from the garage to the dinette area? How much cable did you use? Thanks!

Merry Christmas!

Zigman

I didn't run any separate wiring. I installed my solar charger at the end of the bed platform and ran my solar prewires through the wall between the cargo area to under the bed. If you had some huge array on the roof maybe you would need bigger cable but under 400 watts I think the wire is enough. So really all i did was remove the battery cables on the tongue. Then under the dinette I ran wire the short distance to the 12v panel. It is a little tight under the dinette seat with 2 100ah batters, an inverter, and the wire and Circuit Breakers for the batteries and such, but it all fits.

**zygmunt** · 01-06-2022, 06:11 AM

Hello Dan - Happy New Year!

Thanks for the update. It sounds like a good idea and route I was going to take. I went to NAPA and get extra 4 gauge wire for the battery if I need.

Zig

**Donpworks** · 01-28-2022, 06:27 PM

I'm reviving this thread because the OP's setup is close to what I'm looking do. I've read posts until I'm blue in the face and am thoroughly confused. A lot of threads get way too deep into the woods. This OP follows my usual KISS approach. His idea of hooking the inverter into only one breaker (GFI outlets) took the confusion out about how to isolate the converter from the power center. On my 22MLE the converter is tied into the Main 30 amp breaker and there's not enough room to add it's own separate breaker. This is "Camping" so I imagine we'll get by only powering a few amenities!!!

I too have a 2021 22MLE. I usually stop at parks with at least water and electric hookups but as I research camping spots, particularly on Rec.gov, I see a lot of "non electric" sites that look interesting and I haven't even touched the BLM and sites out west that seem to have more boondocking. I'm looking to set up a relatively simple system that will allow me 2-4 days at a time without plugging into shore power. There's just the two of us.

My Plan:

206ah SOK battery under dinette seat. (the SOK is 12.9" high to top of the covered terminals and the dinette seat bottom is 13.25" inches above the floor (a fat 1/4" clearance) Is that enough?)
Most of the rest of the parts will follow the OP's setup for inverter, transfer switch and solar. I already have a hardwired surge protector. I also have one of the elusive WFCO 8735-LIS Power centers that I'll swap when I set this up. This should allow me to need less solar since the converter should top off the battery.

Questions:

My 22MLE comes with "Solar Prep" which I assume is just wires from the pass through to the roof connector. How would you recommend I get the solar power from the pass through to the battery under the dinette?
Should I put the charge controller in the dinette/ power center area or should I mount the Charge controller in the pass through and then on to the battery? Obviously there would be appropriate fuses etc along the way.
What size wire to pull?
Is there an easily accessible channel or path to the dinette? I don't want to drop the bottom cover if i don't have to.
Should I ignore the front prep and just make a new connection point on the roof above the pantry area and pull wires down through the pantry? That's the shortest distance.

I appreciate the input. I'm close to GO!!

Don

**zygmunt** · 01-28-2022, 07:17 PM

Hello Don,

I am not sure. I didn't get that far. Hopefully someone else who answer this thread can address your concern. Sorry I can't assist you.

**Ynot4me2** · 01-29-2022, 07:41 AM

Originally Posted by Donpworks

I'm reviving this thread because the OP's setup is close to what I'm looking do. I've read posts until I'm blue in the face and am thoroughly confused. A lot of threads get way too deep into the woods. This OP follows my usual KISS approach. His idea of hooking the inverter into only one breaker (GFI outlets) took the confusion out about how to isolate the converter from the power center. On my 22MLE the converter is tied into the Main 30 amp breaker and there's not enough room to add it's own separate breaker. This is "Camping" so I imagine we'll get by only powering a few amenities!!!

I too have a 2021 22MLE. I usually stop at parks with at least water and electric hookups but as I research camping spots, particularly on Rec.gov, I see a lot of "non electric" sites that look interesting and I haven't even touched the BLM and sites out west that seem to have more boondocking. I'm looking to set up a relatively simple system that will allow me 2-4 days at a time without plugging into shore power. There's just the two of us.

My Plan:

206ah SOK battery under dinette seat. (the SOK is 12.9" high to top of the covered terminals and the dinette seat bottom is 13.25" inches above the floor (a fat 1/4" clearance) Is that enough?)
Most of the rest of the parts will follow the OP's setup for inverter, transfer switch and solar. I already have a hardwired surge protector. I also have one of the elusive WFCO 8735-LIS Power centers that I'll swap when I set this up. This should allow me to need less solar since the converter should top off the battery.

Questions:

My 22MLE comes with "Solar Prep" which I assume is just wires from the pass through to the roof connector. How would you recommend I get the solar power from the pass through to the battery under the dinette?
Should I put the charge controller in the dinette/ power center area or should I mount the Charge controller in the pass through and then on to the battery? Obviously there would be appropriate fuses etc along the way.
What size wire to pull?
Is there an easily accessible channel or path to the dinette? I don't want to drop the bottom cover if i don't have to.
Should I ignore the front prep and just make a new connection point on the roof above the pantry area and pull wires down through the pantry? That's the shortest distance.

I appreciate the input. I'm close to GO!!

Don

I also have a 22mle and at the early stages of planning the same. Our solar hookup is on the side not the roof. The wires simply go to the battery box on the tongue. I'm planning on either running new cables via the underbelly. Pretty much following the original cables. Another option that I might entertain is via the side of the black tank vent which is just on the inside wall of the pantry.

Sent from my SM-P610 using Tapatalk

**Harvestmoon** · 11-18-2022, 04:33 PM

Originally Posted by SailorDan

INSTALLION: I removed the lead acid battery from the tongue and installed the Battle Horn under the rear dinette seat. The inverter is also there. First I disconnected the shore power and the 12v battery. I removed the 2 drawers above the electrical panel and pulled the panel out of the wall. Under the dinette I ran 12v lines from the inverter to a post and the battery to the same post (one + and one - post) I ran #2 AWG between the post and battery and inverter to post. On the positive side I have a 200amp circuit breaker/switch installed between the post and battery. From the post to the 12v system I ran #8 wire, the negative to the ground bar and the positive I tied into the Red # 8 wire feeding the 12v panel using a split bolt. For the 110v side I cut the panel feed wire about a foot back from the panel and wired the EMS in line. I did the same thing for the outlet breaker and tied in the Xantrex ATS. The cord from the Xantrex goes through the wall and plugs into the inverter. This was harder than the solar install given the cramped space.

Reviving this older thread again because I am looking at doing a very similar installation on our 2023 22MLE. Under the rear dinette seat seems to be a natural place to host a battery or two and an inverter. The converter is right next door so it keeps the cable runs short, puts the battery in a temperature controlled space, and the battery weight is over the axle instead of sitting on the tongue.
The 2023s are coming from the factory with a 165W solar panel, 30A MPPT controller, and a lithium auto-detect converter, so GD did most of work already. I had the dealer tack on a second 165W panel for good measure, since the 2023s are also coming with the DC-only compressor refrigerators, which cause us boondockers to sharpen our pencils on daily energy demand.

@SailorDan, a couple of follow up questions on your installation:
• I like your use of the split bolt to tie all of the heavy positive leads together. How did you insulate it?
• Did you ventilate the under seat space that houses the battery and inverter to prevent heat build up?

**SailorDan** · 11-18-2022, 07:21 PM

Originally Posted by Harvestmoon

Reviving this older thread again because I am looking at doing a very similar installation on our 2023 22MLE. Under the rear dinette seat seems to be a natural place to host a battery or two and an inverter. The converter is right next door so it keeps the cable runs short, puts the battery in a temperature controlled space, and the battery weight is over the axle instead of sitting on the tongue.
The 2023s are coming from the factory with a 165W solar panel, 30A MPPT controller, and a lithium auto-detect converter, so GD did most of work already. I had the dealer tack on a second 165W panel for good measure, since the 2023s are also coming with the DC-only compressor refrigerators, which cause us boondockers to sharpen our pencils on daily energy demand.

@SailorDan, a couple of follow up questions on your installation:
• I like your use of the split bolt to tie all of the heavy positive leads together. How did you insulate it?
• Did you ventilate the under seat space that houses the battery and inverter to prevent heat build up?

Hi,

I added a second battery after this post and just added it to the picture share in google photos and also attached it. The battery fit nicely behind the water pump after I juggled the lines around a bit. Check out the SOK batteries. https://www.sokbattery.com/ They have the newer heated lithium too.

Q1: The post is isolated at the base, it would just be the nut that would be exposed. I actually don't have anything in the area that isn't strapped down and it was beside the battery so not much chance of shorting out. Really if you look at the top of the battery it is the same. You could probably come up with a way to cover it if you are concerned. Maybe slide a cover over a cable like a car would have. Keep in mind I have a circuit breaker between the post and battery and I switch it off at the end of the season. Here is a link to the Junction Post: https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Q2: I only have a 1200w inverter and mostly I run the TV, Blu-Ray player, and sound bar with sub which is under 200 watts. So I have never noticed much heat coming from the unit. There is an opening from between the dinette and the area of power panel so there is some ventilation. I have a wireless thermometer that displays 4 temps so it wouldn't be a bad idea to add a sender in there just to see.

I have 2 friends that have 12V Fridges. One has an Ember with Solar and Lithium or AGM batteries and most likely 2 batteries or the equivalent. He is never hooked to shore power and no generator and does fine, batteries are always full. The other had a terrible dealer and had the one flooded battery and no solar. They didn't even make it through the night. Adding the second panel was a good move and a second battery should be insurance.

Sadly I didn't even get my rig out this summer. Just too much going on. I was busy finishing the blue thing in the second photo and just did some smaller trips (VRBO,etc). The build blog for the truck is at https://squarenuts.wordpress.com/ if you are into cars at all.