RV life is much more comfortable when your camper’s AC works efficiently. But there are some important operating principles that differ from residential air conditioners. This guide will answer general frequently asked questions about RV air conditioners.
Can You Run an RV Air Conditioner on 30-amp Power?
If your RV requires 30-amp service, that will be enough to run its air conditioner. With multiple air conditioners, you’ll likely need 50-amp service. If your RV requires 50-amp service, you may be able to use a 30-amp adapter to run a single air conditioning unit, but not multiple.
Can You Run an RV Air Conditioner on 15-amp Power?
Theoretically, 15 amps is enough to run an average air conditioner. The problem is figuring out whether your specific A/C is “average.” You’ll need to know the exact amperage required. Unfortunately, you won’t be able to run your A/C on 15-amp power if you have a larger model.
Even if your AC draws less than 15 amps, you may be unable to run any additional electrical appliances without overloading the circuit. For example, the combined draws of your A/C unit, RV refrigerator, and electric water heater may be enough to trip a breaker.
There’s also the question of surge watts versus running watts. An RV air conditioner that draws less than 15 amps while running still draws more when starting up.
To combat this issue, some owners install an RV air conditioner soft start device or manually soft-start by turning on the fan for about 30 seconds before switching to the lowest A/C setting and gradually adjusting for comfort. However, installing soft-start devices or manually operating an A/C with less than the designated power-supply minimums may void your warranty, damage the equipment, and possibly cause a fire.
Your best bet for safely running your RV’s air conditioner is connecting to the electrical service your RV is designed for.
Can I Run My RV Air Conditioner on 120?
Standard 120 electric power supplies about 15 amps. So, running your A/C while plugged into a standard 120 outlet is possible if it draws less than 15 amps and you’re not running too many additional RV appliances simultaneously.
The problems are the same as running on a 15-amp shore power connection. You’ll need to consider surge watts, you won’t be able to run many other appliances, and you’ll need to know exactly what else is drawing on that circuit. If someone plugs a box fan into an outlet on the same circuit, it could be enough to trip the breaker.
Does an RV Air Conditioner Run on Propane?
RV air conditioners run on 120-volt AC power from shore power, a generator, or an inverter, not propane. Propane fuels your RV’s furnace burner (though the furnace’s fan and ignition still run on 12V DC power), and on some rigs, the water heater and refrigerator. But the air conditioner itself runs entirely on 120V AC power to operate its compressor.
How Do I Use an RV AC Safely?
Here are a few tips for safe use:
- Turn off all appliances before starting your air conditioner. RV air conditioners draw more when starting up (surge watts) than they do once they’re operating (running watts). Turning off appliances reduces the chances of overloading a circuit when the unit starts.
- Inspect the shroud regularly. The shroud protects the A/C components mounted on your roof. Check it before and after each trip to ensure it isn’t cracked or missing. Cracks allow dust, moisture, and other debris to degrade sensitive A/C components.
- Keep doors and windows closed. Minimize the stress on your unit by trapping cool air in and keeping warm air out.
- Park in the shade. This also reduces how hard your air conditioner needs to work by limiting your RV’s exposure to direct sunlight.
How Many Amps Does an RV Air Conditioner Use?
The average RV air conditioner draws between 11 and 16 amps, but some units (smaller and larger) fall outside that range. Energy efficiency also comes into play. You can have two A/C units of the same size, but the more efficient model will usually draw fewer running amps.
Here’s a quick breakdown of the average A/C amp draw relative to unit size in British thermal units (BTUs):
Technician Tip: Amp ratings are listed for 70℉. Add 1 amp for every 10℉ outside temp above 70.
| AC Capacity (BTUs) | Running Amps |
| 5,000 | ~4.35 |
| 6,000 | ~5.22 |
| 8,000 | ~6.96 |
| 10,000 | ~8.70 |
| 12,000 | ~10.43 |
| 13,500 | ~11.74 |
| 15,000 | ~13.04 |
| 18,000 | ~15.80 |
| 20,000 | ~17.39 |
How Many Watts Does an RV Air Conditioner Use?
Calculating camper AC wattage requires multiplying amps by voltage. RV air conditioners run on a 120-volt circuit, which you can multiply by the A/C’s amperage to convert to wattage. You’ll notice that you can also divide an air conditioner’s BTU rating by 10 to get an approximate measure of running wattage.
This is helpful when determining whether you can safely run your air conditioner with a generator, which usually has a wattage rating rather than an amperage rating.
Here are some average RV air conditioner wattage ratings by A/C size:
| AC Capacity (BTUs) | Running Wattage |
| 5,000 | ~500 |
| 6,000 | ~600 |
| 8,000 | ~800 |
| 10,000 | ~1,000 |
| 12,000 | ~1,200 |
| 13,500 | ~1,350 |
| 15,000 | ~1,500 |
| 18,000 | ~1,800 |
| 20,000 | ~2,000 |
Will a 3500-watt Generator Run an RV Air Conditioner?
The short answer is yes, for most. But you’ll need to know your air conditioner’s surge and running watts. Larger units draw more power and may limit your ability to run other RV appliances, even with a 3500-watt generator.
Here are some generator size recommendations based on your RV’s electrical demands:
- 30-Amp RVs: Minimum 3,500-watt generator
- 50-Amp RVs: 6,000 to 8,000-watt generator for RVs with dual ACs; 10,000 to 12,500-watt generator for RVs with three ACs.
Learn more: What Size Generator Do I Need for My RV?
How Long Can You Run an RV Air Conditioner?
When camping, you can run your A/C 24 hours a day. You’ll just want to use a modest thermostat setting that allows the compressor to cycle on and off periodically. For larger RVs with two or three units, you can cycle between them to give the units intermittent breaks. As a supplement, you can also use a camper dehumidifier to assist your air conditioner in removing moisture from the air inside your RV.
Most RV air conditioners last 6-8 years if maintained properly. The more diligent you are with service and maintenance, the longer you’ll be able to run your A/C.
Having a reliable power source is the most important factor for keeping your A/C running efficiently. This isn’t an issue when you’re plugged into 30 or 50-amp service, but you’ll be limited to your generator’s run time if you power your A/C using an appropriately sized RV generator.
How Do I Make My RV Air Conditioner Colder?
If your air conditioner isn’t lowering the temperature inside your RV to a comfortable level, here are a few things to try:
- Adjust your RV thermostat. It could be as simple as telling your air conditioner to make it colder inside your RV.
- Move to a more shaded location. Reducing your RV’s exposure to direct sunlight will make your A/C more effective because it won’t have to work as hard.
- Add insulation to windows and roof vents. This traps cool air inside instead of allowing it to escape.
- Clean and/or replace the air filter. Insufficient airflow reduces your air conditioner’s effectiveness.
- Clean the coils or fins. Clogged condenser or evaporator coils will also reduce A/C efficiency. These should be checked and cleaned every other year.
- Check your power supply. Insufficient power will cause your A/C to operate below its cooling capacity.
- Minimize the number of occupants. The more people you have inside, the harder your A/C has to work to cool things down.
- Cook outside. It’s easier if your RV features an outdoor kitchen, but it’s worth it.
- Shower in the bathhouse. Eliminates steam and condensation from hot water, unless you like cold showers.
- Minimize the use of appliances and electronics. Every appliance in your RV gives off heat when it’s on. Reducing electronic usage will make life easier for your RV air conditioning unit.
- Upgrade your RV air conditioner. In some cases, you may decide to replace your existing A/C with an upgraded model.
Read our tutorial on improving RV air conditioner efficiency.
Can You Add a Thermostat to an RV Air Conditioner?
Most A/C units have a built-in thermostat or are wired to a wall-mounted thermostat in your RV. Aftermarket residential thermostats rarely work with RV air conditioners, and while upgrade kits are available, they must be from the manufacturer and be designed specifically for your AC make and model.
These kits will likely require installing additional components to communicate properly with your AC. If your thermostat needs to be replaced, your best bet is to consult the owner’s manual and wiring diagrams for your model and contact your local service center.
When Do I Need a Professional RV AC Repair?
Most of the questions above are about how your AC works day to day. But sometimes the issue goes beyond basic operation. Consider scheduling a professional diagnostic if you notice:
- Your AC keeps tripping the breaker even though you’re connected to the right power service.
- The fan runs, but the air never actually gets cold—our guide on why your RV AC isn’t cooling walks through the most likely causes.
- You hear a new rattle, buzz, or grinding sound—see why your RV AC is making noise to help identify what it means.
- Water is dripping inside your RV instead of draining outside as normal—see why your RV AC is dripping water inside to help pinpoint the cause.
- It won’t turn back on at all after a power outage or a full reset attempt.
If any of these sound familiar, don’t keep running the unit. Operating a struggling AC can turn a minor issue into a more expensive repair. Camping World’s certified technicians can diagnose the issue and get your AC back to cooling.
Additional RV AC General FAQs
RV air conditioners typically range from 5,000 to 18,000 BTUs. Some larger units will run multiple units, and you can see the full range in the amp and wattage tables above. On the smaller end, portable and window-mounted units are common, since roof-mounted units rarely go below 13,500 BTU. Small portable and window-mounted AC units are great options for RVs without AC or for supplementing an existing RV air conditioner.
Most RV manufacturers list heights measured from the ground to the highest point, typically your air conditioner. Some will publish both measurements — with and without the A/C height. A potential exception would be if the base model doesn’t include an air conditioner, but one is available as an upgrade. In that case, the listed height may not include the air conditioner.
You can run your camper’s air conditioner while driving if you have a built-in generator and it’s running. You should NEVER run a portable generator while driving to power your air conditioner. If you’re riding in the cockpit, the dash AC should be enough to keep you and your navigator cool until you reach your destination.
Got any troubleshooting questions? Check out our RV Air Conditioner Troubleshooting Guide.
Do you have questions about RV air conditioners that we didn’t address? Let us know in the comments below.
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