How to Install RV Solar Yourself: DIY Guide
Ready to install a solar system in your RV? You’ll need these RV solar panel installation instructions.
DIY solar installation can be really daunting and intimidating, but once you understand each step, it’s very straightforward.
Now, if you’re searching for RV solar panel installation instructions, I’m not sure if you need instructions on simply mounting your solar panels or installing the whole system. So this guide will cover both mounting the solar panels, while providing instructions on installing your whole solar system as well.
You should already have a good idea of how your solar system is mapped out in your RV, including how everything will connect, and where it will go.
You should know how many solar panels you’ll have, how they will connect to each other (series or parallel), how they will reach the final wires which will enter your RV roof, and how to tie your specific battery bank together.
If you don’t want to figure any of this out yourself, you should buy a solar kit which will come with the panels, the wires, and the charge controller, along with great instructions and support. That is how the author of this article got started and it makes everything extremely clear and simple, and you can add more solar panels from there!
What you’ll need:
- Solar panels
- Z brackets or other mounting hardware
- Lag screws (for rubber roofs with wood underneath) or VHB tape (for fiberglass RV roofs)
- Solar wiring, mc4 connectors
- Cable entrance housing
Installation Instructions for RV Solar Panels
1. Physically map out your RV solar system
Map out the location of everything in your system, including where your solar panels will go on your roof, and where your wiring will enter the roof to go into the RV and connect to your solar charge controller.
This means making sure that no shadows will land on the panels from other roof accessories, and your wire will reach to your cable entrance housing.
Lay your panels out as planned and mark where they will go.
Stage everything including where you’ll mount your charge controller and where your batteries will go. Before installing your solar panels on the roof, your batteries should already be in place in your RV.
2. Prep the wiring
You’ll need to prep your solar panel wiring before mounting them to the roof. This means having all MC4 connectors ready to go (these should already be on your solar panels) and ready to be connected to each other.
You should also have the wiring ready to go from your solar panels, into the weatherproof cable entrance housing, down into the RV.
3. Install the cable entrance housing & interior wiring
You’ll need to drill a hole in the roof or enter another existing hole (such as a fridge vent or the side of a tank vent) for the wiring to enter your RV.
If you’re going with a new hole and entrance housing, now is the time to drill that hole and insert the wiring so that it goes from the roof down into the RV. The bare ends should be accessible to the control panel location inside, and the ends still on the roof should have MC4 connectors which you’ll connect your solar panels to.
Once the hole is drilled and the wiring is entering the RV appropriately, you can mount the cable entrance housing using Dicor.
4. Mount the solar panels to the roof
Now, with all of the wires staged/reaching each other, and the junction box leading the wiring into the RV, you can mount the solar panels in their final location.
If you have a rubber roof with wood underneath, you can mount the panels to your roof by screwing lag bolts into the Z brackets, which are the feet of the panels. Or, use any other hardware that you’ve come up with for attaching the panel to the roof, if you have a custom solution for tilting the panels. However, un-tiltable Z brackets are easiest and often come with many solar kits.
Screw each lag bolt into each Z bracket on each panel. Then, cover the entirety of the foot with dicor. Don’t just cover the top of the screw, because remember, water can also seep under the foot of the solar panel. You can also use butyl tape under the foot when mounting for added protection.
If you have a fiberglass roof, you’ll mark the location of each bracket, clean it with alcohol, let it dry, and then apply VHB tape according to the instructions so that the panels stick to the roof. Don’t worry, they really will stick when applied appropriately!
5. Install the rest of the in-house solar system
Before you connect the solar panels to the wiring entering the RV, you’ll want to first complete the setup of your battery and charge controller. Your charge controller should have instructions for mounting and installing the wiring from the batteries.
It’s very simple – you’ll just connect wires to the batteries as appropriate, and then run those wires to the charge controller.
Once the batteries are correctly wired to the charge controller, you’ll head back to the solar wires to connect those to the charge controller next.
6. Wire up the solar panels
If it’s a sunny day, it may be a good idea to cover your solar panels with blankets or cardboard while wiring them up since they are conducting electricity.
Go ahead and connect the solar panels in series or parallel to each others MC4 connectors, then connect the final MC4 connectors to the wires that lead inside the roof to the charge controller.
Once that’s done, you can go back inside to the charge controller, and complete the hardwiring of the solar wires to the charge controller, the same way that the battery ones were connected.
Remove the coverings on the solar panels, and if everything was done right, you should be conducting power!
Confused on your DIY RV Solar Panel Installation?
Based one when I installed my RV solar panels, I know that instructions can seem really daunting when you don’t have the pieces in front of you. But at the end of the day, the solar installation really is as simple as solar panels > charge controller > batteries. They all connect to each other, and the confusing part is how they wire into each other.
When the solar panels connect to each other, they use MC4 connectors. These are simple connectors that clip into each other. You’ll also clip the final panel MC4 connectors into the wires that go down into the roof.
Then, once the wires go down into the roof, you’ll have bare wire ends that will screw directly into your charge controller. Your charge controller instructions will come with details on exactly where to put these on your controller.
The wires coming from the batteries will connect to the charge controller in the same way that the solar panel ones do – with bare ends.
Finally, the end of the wires that go on the batteries will be connected with heavy duty terminal connectors that should go around each battery terminal.
Once you have seen it in person, it is far easier to understand. Just pay attention to polarity, follow your instructions on each of your parts closely, and make sure you’re using wiring and fuses that are appropriate for your kit. This is the benefit of buying a kit from the start.
Let me know if you’ve installed solar on your RV yourself and what you thought of these instructions!
Can you leave the #7 wire from your vehicle connected to the trailer while driving and your solar panels are also charging. I can’t seem to get a straight answer. Some say it won’t cause a problem with your truck alt. Some say disconnect the truck fuse for the #7 wire. What to do!
Hey Jan and Martha, thanks for the question. I wouldn’t feel comfortable answering that without seeing your wiring setup, so I would say your best bet it to have a trailer dealer or solar installer take a look to see if they can give you a proper recommendation.