What Size Generator Do You Need to Run an RV Air Conditioner?
Let's face it: even the most outdoorsy adventurers among us don't love the idea of sweating in a cramped tent in sweltering summer temperatures. One of the biggest perks of RV camping is the fresh, cool air provided by your air conditioner. With your motorhome's AC unit, you can enjoy a relaxing day (or night) in your camper, sipping an ice-cold drink and congratulating yourself on your decision to buy an RV.However, if you plan on boondocking and enjoying your RV off the beaten path (and away from shore power), you probably want to run your AC to keep things cool. For this, you'll need a generator.So what size generator do you need? One that's big enough to run your AC as well as everything else you plan to run. You don't want to enjoy your AC but lack the ability to use your lights, charge your phone, or power your fridge!We'll help you get started figuring out your AC power demands below.
How Many Watts Does an RV AC Use?
To choose the right size generator, you need to know the starting (surge) watts and running (rated) watts required by your RV's air conditioning unit.Every air conditioner is different, but they all require a specific number of "start up watts"—the initial burst when the unit is turned on. Each unit will also require a certain number of "running watts," which will be lower (sometimes significantly) than the start-up watts needed.RV air conditioners are typically either 15,000 Btu (British thermal units) or 13,500 Btu, although other sizes exist as well. This is basically the cooling capacity of your AC. A 15,000 Btu unit has a greater cooling capacity but will require more power—about 5,100 starting watts and about 1,600 running watts, on average. A 13,500 Btu unit draws less power—about 3,800 starting watts and about 1,300 running watts.You'll need to make sure your generator can handle both the starting and running requirements of your unit, as well as the starting/running watts of all your other appliances you plan to run. Check the manufacturer's label or manual provided for your appliances to verify how much power they draw.In general, it's better to have more power than not enough. If you're wavering between two generator sizes and think you can get by with the smaller size, strongly consider going one size up. The extra power will allow you some breathing room if you end up using more power than you initially plan. (Or if you forget to let the washing machine finish before turning on the microwave.)
Note: These numbers are averages based on information obtained from RV AC manufacturers as well as our own testing. Starting wattage on air conditioners can vary greatly depending on several factors, including the assistance of built-in capacitors and cold starts.
Calculating Generator Requirements to Run Your AC
If you plan on running your AC and other appliances with a generator, your generator must meet or exceed the demands of the devices it will power. That means that you need to calculate the average power demand (watts) of all the appliances you plan to run, not just your AC.It's always best to start your generator without a load connected, then add your devices one at a time. It's also a good idea to connect your devices in order from highest starting watts to lowest starting watts. Most likely, your AC will require more starting watts than anything else, so typically you'd want to start up your AC first.As an example, let's say we plan on running the following appliances with the following power requirements with our generator:
ApplianceRunning WattsStarting Watts
13.5k BTU AC1,300W3,800W
Refrigerator800W1,600W
32" LCD TV150W0W
Floor Fan100W0W
To find the total starting watts required, add the starting watts for the device with the highest value (in this case, our AC unit) to the running watts of the other devices.
To find the total running watts required, add together the running watts for all appliances.
Ex: 1,300 + 800 + 150 + 100 = 2,350 running watts
In this example, we'll need a generator with at least 4,850 starting watts and 2,350 running watts. For help with more precise calculations, typical power demands of RV appliances, and additional need-to-know information on generators, check out our generator overview.
Which Generator Will Run My RV Air Conditioner?
At etrailer, we perform numerous tests on generators to put them through real-world experience. An extensive part of this testing includes starting and running RV air conditioners.The following table will help you decide which generator has enough power to handle this critical function in your RV. Select the generator type you need from the chart below, then scroll down to find the available generators that can handle your load.NOTE: Decibel (dB) levels are measured at 25 ft away in standard mode at 1/4 load, unless otherwise indicated. Normal conversation is 60 dB. GROUP A
About the AuthorAs a content writer for etrailer, I might spend my morning loading and unloading a bike on five different bike racks to figure out which is easiest to use. I might be in the parking lot, taking pictures of an impressive RV battery setup our techs came across in the shop and discussing the benefits of the setup with the owner. I might spend an afternoon in a manufacturer training classes for some hands-on experience with new products, and then sit down to assemble all this information into a coherent article.At etrailer, one of our core values is that we are always learning, and I learn something new every day. I start each morning with the goal in mind of taking all of this information and figuring out the best way to answer the questions people ask us (and the ones they don’t know to ask yet), and helping people get the solutions they need to make their lives easier, safer, and more fun. I’m a DIYer at heart, so it brings me great joy to help a fellow DIYer find what they’re looking for, whether that’s a product, an answer, or a community.
Is there any way to run a parallel system using solar for 50 amp, around 6k watts total? I'm looking for a portable solar inverter generator(s) plus panels that I can parallel a 50 amp connection for our RV... The RV has two A/C units (a 15k BTU, and a 13.5k BTU). Thanks!
I'm not aware of any generators that you can connect solar panels directly to so the only way I really know how you'll be able to do this is by using a whole setup with an AC/DC converter panel so that you can have both AC and DC connections for your trailer power.
@JonG thanks for your response. I've found several but not the right wattage. Jackery Portable Power Station Explorer 1000, and I believe generac carries them as well..
@Will We actually do have some portable power stations like the Jackery that you mentioned - I thought you were referring to a standard-type generator. These are designed more for smaller applications or emergency power in the event of a power failure and aren't really meant to power a whole camper. They are essentially big batteries with a smart charger built in and multiple ways for you to draw power from it. For your application it sounds like you'd want to go with a big battery banks and then add solar to that as well.
Hey Bryan, Dometic has the CT Thermostat and Control Board part #DMC83ZR as a fit for all single zone Dometic units so yes it would work well on your Duo Therm.
Hey Christopher, thanks for reaching out! The Dometic CT Thermostat and Control Board #DMC83ZR will allow you to control a Dometic Penguin II, like the part #DMC89ZR, yes.
The #ADV79FR is just the unit itself which could be used as a replacement for an existing setup. The Advent Air Low Profile RV AC w/ Air Distribution Box, Start Capacitor, and Heat Strip - 13,500 Btu #ASA49YR has everything you need to add a new…
It's a warranty issue. You can install the Advent Air Low Profile RV Air Conditioner item #ADV79FR, on your food truck, but you will void your manufacturer warranty since ASA will only honor warranties if the units are installed on a camper…
Hey David, it sounds like you know what you're doing but I've also gone ahead and found the wiring diagram for the Replacement Single Zone Thermostat for Dometic RV Air Conditioners #DMC79FR for you to check out so you can use it as a…
Based on the square footage of your 28 foot utility trailer the minimum BTU rating you'd need from an AC unit would be 4,760. So the Advent 15k BTU unit part #ACM150C would easily handle cooling your trailer. There'd be no need to add…
I took a look at the manual for the Lippert Ground Control 3.0 Electric 5th Wheel RV Leveling System part #LC358590 and on page 4 it states the proper procedure to extend each of the jacks separately. I have attached this procedure for you below:…
Yes, the Replacement Right Rear Leg #LC344792 is the correct unit to replace the rear passenger side jack on your Lippert Ground Control 3.0 System. I reached out to my contact at Lippert and he said there aren't any specific torque specs…
Thank you for providing those measurements! Since your 5th wheel hitch height is 47 inches, subtracting the bed height of 39 inches gives us the 8 inches you mentioned which is technically the setting you would need to use on your Demco Hijacker…
The 13,500 Btu Advent Air RV Air Conditioner w/ Air Distribution Box, Start Capacitor, and Heat Strip #ACM135BCH (Black) and #ACM135CH (White) draws 1,450 watts so you will need a generator with that much capacity so keep the AC up and running. For…
Since the 2023 Palomino backpack pop up camper 1240 is a smaller camper compared to travel trailers you could get away with a smaller BTU unit like the Advent Air RV AC unit part #ACM135C which comes with everything needed to install as well. It…
I suggest the Advent Air RV Air Conditioner w/ Air Distribution Box and Start Capacitor, #ACM135C. This is a 13,500 Btu ductless air conditioner that has a distribution box with built-in thermostat to control the fan and temperature and a start…
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10/4/2020
Is there any way to run a parallel system using solar for 50 amp, around 6k watts total? I'm looking for a portable solar inverter generator(s) plus panels that I can parallel a 50 amp connection for our RV... The RV has two A/C units (a 15k BTU, and a 13.5k BTU). Thanks!