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Our Outdoors RV 21RBS has several 110V electrical outlets scattered around - by the bed, under the desk (after our remodel), in the kitchen, in the bathroom, and outside.
That's great, as it gives us lots of choice for plugging things in - either using our inverter or when we're hooked up to shore power.
However, what's not so great is that all these outlets are on a single 15 Amp circuit. This means we can't plug in two or more high-power appliances at once, since they'd draw more than 15 Amps and trip the breaker.
We're planning on spending this winter in much colder temperatures (with hookups), and as such would like to run our small plug-in electric heater to help reduce our propane consumption.
The electric heater pulls about 1,500W (~13 Amps @ 110V AC) when running on high power, which means we can't run any other large plug-in appliances when the heater is on. So we'd have to turn off the heater to run our Instant Pot, Air Fryer Lid or electric kettle. Not ideal!
The solution? We're going to install another double outlet on its own 15 Amp breaker, so then we can run two large plug-in appliances at once. We can stay warm and run the Instant Pot!
Things to Know
Disclaimer: Problems in the electrical system can cause fire, injury or even death. This blog post is for informational purposes only and anything you do is at your own risk. You should do your own research and if at any point you are unsure then STOP and consult a qualified professional.
Our RV 21RBS is a 30 Amp RV. This means that when we plug into shore power, we use a 30 Amp plug. It also means that the main breaker in the 110V AC breaker panel is rated to 30 Amps.
This means that all the 110V appliances running at once in the RV can't add up to more than 30 Amps. By way of example, large appliances such as the air conditioning unit or microwave might pull 10-15 Amps.
The 30 Amps is then distributed amongst other breakers - for example, the air conditioning has a 20 Amp breaker, the microwave has a 15 Amp breaker, and the outlets are on their own 15 Amp breaker. Your RV may be different.
If yours is a 50 Amp RV, then the process is very similar but you'll have two sets of breakers - one for each hot leg.
By adding another 15 Amp breaker, we are able to run multiple large 110V plug-in appliances at once, but the maximum still can't exceed 30 Amps - the rating of the main breaker.
This is particularly interesting in our RV, since we have a Victron MultiPlus 3000/12 hybrid inverter-charger which can combine shore power with our batteries using its Power Assist mode to output far more than 30 Amps. However, to make use of this, we'd have to upgrade the wiring and AC panel itself - something beyond the scope of this mod....maybe one for the future!
Last, there is a warning label on our AC breaker panel which says we must use a listed energy management system if we want to install more than 5 branch circuits. This new breaker will add a 6th (and 7th) branch circuit. This guidance is to prevent people from trying to pull more than 30 Amps total - which is easier to do if you have more branch circuits installed.
In our case, we know exactly what we're doing and why we're doing it, so I'm not too concerned. However, proceed at your own risk.
Parts & Tools
This mod requires only very basic tools - things that I'd recommend any RVer carries anyway but are available at any good hardware store if you don't have them already.
|Screwdriver (#2 square bit)||Amazon|
|Screwdriver (Philips bit)||Amazon|
|Wire Stripper & Cutter||Amazon|
|Siemens Q1515 Two 15-Amp Single Pole 120-Volt Circuit Breaker||Amazon|
|14/2 Romex||Amazon | Home Depot|
|14 cu. in. 1 Gang Old Work Box||Home Depot|
|15 Amp Tamper Resistant GFCI Outlet||Home Depot|
|1 Gang Wall Plate||Home Depot|
I chose to buy a tandem 15 Amp breaker online to match the exact breakers used in our RV, but you can buy a different model as long as it's the correct type (Type QT). While the second breaker isn't used in this mod, I have ideas for that later!
I'd also highly recommend a GFCI outlet for safety. In our case, we would be installing it near the kitchen so it was critical.
I had some spare 14/2 Romex left over from the desk build, so I was able to use that. Overall, the parts for this mod should cost less than $50.
Once again, working with electricity can be dangerous and if you don't feel absolutely comfortable then please STOP and consult a qualified electrician.
Before going ANY further, physically disconnect your RV from shore power, unplug your generator and disable your onboard generator or inverter. In our case, I shut off our big red inverter disconnect switch. Use your multimeter to confirm that there is no 110V power coming into your AC panel, and make sure nobody is going to accidentally plug you back in again!
Step 1: Decide on location
One of the most challenging things about electrical work in an RV is pulling electrical wires. For this mod, you'll need to run a wire from the AC panel to the location of your new outlet. So depending on where you choose to put your new outlet, this mod can either be really straightforward or much more difficult! In our case, I wanted to make it as simple as possible!
I chose to install the outlet immediately adjacent to the AC panel. Not only would this make the install much easier, but it's also a very useful location! We have no floor-mounted outlets, and not only would that be a good location for our electric heater (we have no kids or pets to knock it over), but we can also put the Instant Pot on the floor when in use to free up countertop space in the kitchen.
I also deliberately avoided mounting it on one of our exterior walls - that would complicate things greatly. In fact, most 110V outlets installed by the RV manufacturer are special sealed units to cater for the shallow wall depth, requiring a very expensive tool to crimp correctly! The space where I wanted to mount ours was totally empty behind - and really easy to access should I need to.
Step 2: Install new breaker
I double checked (again) that the power is turned off to the AC panel! Then, I removed the front panel so I could access the breakers and wiring behind.
The black box underneath the breakers in the photo above is our Progressive Industries EMS-HW30C. When we installed our Victron MultiPlus we were able to remove the existing converter so we used this spot to install our EMS.
At this point, I fed the 14/2 Romex wire through from behind the panel, and stripped off about 6 inches of the outer insulation, followed by about 3/8-inch of the inner insulation on the black (hot or live) and white (neutral) wires.
The new breaker snapped easily into place below the existing breakers.
Using the square tip screwdriver, I connected the bare copper (ground) wire to a vacant spot on the ground bar, the white (neutral) wire to a vacant spot on the neutral bar, and the black (hot) wire to the top terminal on the new breaker.
It's important that all wires are securely held in place and making a good condition. I took the opportunity to double check all the existing connections were secure and tight too.
Step 3: Mount & wire up outlet
I used the old work box as a template to draw the location for the new outlet. Then, I used the drill to drill a hole in each corner and a jab saw to cut out the hole. It should be a fairly tight fit else the wings of the old work box won't grab securely.
I inserted the old work box into the hole I'd cut out and tightened the screws to extend the wings and clamp them against the back of the surface.
I then routed the 14/2 Romex from the back of the AC panel, and pulled it in through one of the access ports on the back of the old work box. Once again, I stripped back the outer insulation and the insulation on the end of the black and white wires, then wired it up to the GFCI outlet.
Once wired up, I was able to carefully fold up the excess wire and press the outlet into position. I screwed it into the old work box, ensuring it was straight and centered, then last I attached the face plate over the front.
Step 4: Test and tidy up
With everything wired up, I put the plastic front panel back on the AC panel - but had to pop out another spacer for the new breaker. It was a tight fit (I think the spacers are a little smaller than they should be), but I managed to get it mounted.
Then it was time to test!
I switched on the power to our inverter, and then turned on the inverter itself. I checked the GFCI was operating correctly, then plugged in a battery charger to make sure it was all working. It was!
This mod took under an hour and since I already had some leftover 14/2 wire, it cost me less than $40.
We added this outlet about 2 weeks ago and have already been making good use of it. It's great to be able to have the Instant Pot on the floor while it's running to free up some countertop space. Plus, it's also a convenient location for temporarily putting battery chargers - e.g. the charger for our DeWalt cordless drill.
I can already tell we're going to be making good use of the new outlet this winter to run our heater!
At some point, I may use the extra breaker to split our outside outlets onto their own circuit too, as in summer we often run the Instant Pot outside to avoid heating up the RV.
I'd like to upsize the wiring from the inverter to the panel and upgrade the 30A main breaker so I can take full advantage of our inverter's Power Assist feature even when we have 30 Amp shore power, but our AC panel is only rated to 30 Amps. If I can find a replacement panel that will fit in our current location, this is something I'd strongly consider doing in future!
But for now, this has been a simple and straightforward mod that has helped us make the most of the 30 Amps we have!