Adding a Second AC Unit (RV Pre-Wired For Air Conditioner)

It can be done. However, you may find that electricity may be in short supply when you add a second AC unit to your RV or trailer. Adding a second AC unit will depend on what your RV or trailer is wired to handle. That is if you want to run other electrical devices at the same time.

This is not a hard task to do and you can do it yourself if you want to. Also, if you are skilled at these types of projects, just look for any pre-wiring panels to let you know where the wires for the second unit are.

To learn more about this topic, just continue to read our article. It tackles this topic giving you the information you want to know about before you get started. Take a few minutes to see how this information helps you.

Can You Add An AC To a Travel Trailer?


This is a possibility but there are still quite a few factors you need to consider before you attempt this project. These factors are as follows

- wiring- is your RV or trailer pre-wired for an extra Ac unit or not? Can you add wiring to your RV or trailer?

- amperage- how many amps is your RV wired to handle? If it is 30 amps, you may not be able to run both at the same time. If it is 50 amps, then you can

- size- how tall is the new RV unit? You have to watch out for low clearances so you do not want it too tall.

- inverter- is it powerful enough to help run the AC unit? Or, is your generator powerful enough to run two AC units at a time?

When it comes to pre-wiring, look first before you buy. RV makers were pre-wiring their models as far back as the 70s and those wires may still be in good shape if they were never used.

If it is pre-wired, all you have to do is connect them to the AC unit and the breaker box. If your unit never came with an AC unit, changing one roof vent to AC use is not that difficult.

Adding AC To Travel Trailer

When you are adding an extra AC unit to your RV or trailer, this is not a difficult task to perform. One of the key issues will be the weight of the AC unit. Not just for lifting it up to the roof but for your overall weight capacities and if your roof is strong enough to hold it.

The difficult part will be lifting the AC unit up onto the roof. Make sure you have plenty of help to do this task. Before you get started, look for pre-wiring. It may be in its separate area with its own cover, or it may be attached to one of the vent openings.

It is hard to say where the RV makers placed those AC wires. The other thing to be concerned about will be if those wires are for a vent fan or an AC unit. If for the latter there should be 2 of them there is not one.

Then as we mentioned earlier, you have to check to see what your trailer is wired to handle. If it is 30-amps you may have difficulty running the AC unit and other appliances at the same time.

If it is wired for 50 amps, then you should have no problem hooking up the AC unit and having it work. This is essential for those times you are adding a second AC unit.

On a 30-amp system, you will most likely not be able to run two large AC units at the same time. You may be able to run 2 smaller units if the BTUs are low enough.

Cost To Add a Second AC To The Travel Trailer


The actual cost you will pay will depend on the method you use. If you intend to do it yourself, then the cost will only be restricted to the price of the AC unit and the few wires, connectors, and breakers you will need.

This is the cheapest option you can choose but make sure you have the skills to hook it up right. The next method would be to hire a local handyman to do the work for you.

They are usually skilled at this type of work and their cost for labor will be lower than a professional installer. The drawback to this option is that you do not have a lot of recourse if something goes wrong after he has installed the device.

The final method would be to hire a professional to do the work. They can make the right connections, get the thermostat hooked up correctly, and so on. They will also be faster than you or a handyman.

The drawback is the cost of their time and work. What you will pay will be up to the company you hire to do the work. They all have their own fee schedules and one we read was in the neighborhood of $1500.

Some owners have suggested getting the 2nd Ac unit installed when you order your new trailer or RV. That cost is much lower than adding a second one later. The quote we saw was between $800 and $1000.

Self-Install or Dealer?

This is a very good question. We would not recommend anyone to self-install if they have had no electrical experience or know how to hook up the thermostat. While you will save money initially, the cost to redo your work can get expensive.

Then the dealer can do it for you. They have trained professionals to make sure everything is hooked up just right. The drawback is that dealers may be more expensive than the local AC unit installers

It is easier for you to have someone else do it and sometimes if you are NOT under warranty, it is best to go with a local AC or HVAC company that handles RV AC unit installations.

They can do good work and hopefully charge less than a dealer. The only way to find out is to call both and compare their estimates. Of course, if you are still under warranty, you may be restricted to having the dealer handle the work.

That way it gets done right and you may not have to pay as much for the installation. Check with your RV company to make sure how this is handled with your warranty protection. The last thing you want to do is void that coverage.

RV Pre-Wired For Air Conditioner


This is a good situation to be in. With the wires already in place, you do not have to buy extra wires nor worry about finding the best route to run those wires. Everything is done for you.

What is left to do is simply install the AC unit and it should have a space designed to hold it. That space usually measures about 14 1/4 by 14 1/4 inches in size. If the space is larger than that you will need to add spacers to secure the AC unit.

If it is smaller, then you will have to make the space large enough for the AC unit to fit. Once that is done, all you have to do is connect the wires to the AC unit and the breaker box.

Pre-wired can be found in many older models of RVs. The 73 Coachman Cadet had pre-wiring d9one for an AC unit. We are not sure how many older models had the same feature but you can check to see if yours is ready.

If you have roof vents, just open those up and see if there is a wire or two already installed. If there is, then you should have an easy time adding that first or second AC unit.

Adding a Second AC Unit To RV

This is not a difficult task except, as we said earlier, getting it up on the roof of your RV or trailer. Some people have used ladders and ropes to slide it up. Others have had help in carrying them up the ladder. Which way you use is up to you.

If you use a professional, we are sure they will appreciate any lifting help you can provide. The key is not if your trailer or RV is pre-wired or not but if your RV or trailer’s electrical design can handle the extra electrical load.

The other important aspect will be the size of the Ac unit. Some people say that you can run 2 13,500 BTU units off a 30-amp system. You may not be able to run anything else but you will be cool

Size selection is important and you need to figure out how many BTUs you will need. To do that you have to look at your camping situation. Are you going to be in the hot desert all the time or will you be in cooler climates some of the time?

The weather in your camping area will help you make the right size decision. Then you need to make sure you can control the unit from the inside of the trailer or RV.

There has to be some thought given to all these little details before you go out and buy your second AC unit. The price of that unit will be down the list for now.

How do I Add a Second Air Conditioner To My Travel Trailer?


The best method to use in installing a second AC unit on your RV or trailer is to hire someone else to do it for you. This is not a cop-out as most people do not know how to wire a light bulb, let alone an AC unit.

If you do not know how or are afraid of electrical shocks, then this is your only option. While they cost more, the best option in hiring someone is to hire a professional.

That way you know the work was done right and if it wasn’t you have a way to get your money back or take legal action. Also, you will want to go with a low-profile unit to make sure you do not have any clearance issues.

Then check your warranty as that may make your installation decisions for you. Some AC units can add as much as 10 inches to your overall height. That will cause you some problems when you travel roads where the bridges have low clearances.

Tips For Installing a 2nd AC Unit

1. Start with an existing rooftop vent- if one is not available, the professional will cut a new opening for you

2. Go low profile- it is the way to get peace of mind and opens up your travel options. You can go down those very scenic but very back road routes.

3. Keep the shorter side facing the front- this will cut down on your wind resistance as you drive. Every little bit helps your fuel efficiency.

4. Make sure to use bolts & nuts- these are more secure than just using screws. Also, follow the manufacturer’s installation instructions carefully, especially on the inside part of the installation.

5. use a professional even if you have electrical experience- doing it yourself may not always be a wise idea especially when you are getting up in life.

Some Final Words

Adding a second AC unit is a smart idea for many parts of the country. Those winters may be cold to the natives but to you, they can still be fairly hot. Having an extra cooling source can help you enjoy your vacation a lot better.

Just make sure you get the wiring connected right and the right AC unit for your RV’s electrical system. Everything else is a piece of cake when it comes to installation and purchase.

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