“Cool” Tips to Make Your RV Air Conditioner Run More Efficiently

As we approach the dog days of summer, we find ourselves “recreating” in some extreme temperatures and high humidity conditions. In our homes we can maintain a comfortable temperature just by setting the thermostat and not worry about it. Every time we walk into the house the temperature is the same. Too many new RV owners expect the same performance from their RV roof air conditioner and become frustrated when they step into an uncomfortable rig!

To optimize the performance of your roof air conditioner and help it run more efficiently, you need to understand: how the system works, what limitations it has, and how surrounding factors can affect your overall comfort.

How the System Works

The compressor “compresses” the refrigerant into a vapor and then the condenser removes the heat and condenses it to a liquid. As it passes over the evaporator coils, heat is drawn from the return air to make it expand vaporize. The removal of heat from the air provides the cold air to the RV. The system is completely closed so there is no “recharging” refrigerant like you would do for an automotive system.

The biggest culprit in low cooling in an absorption system is a dirty return air filter or even dust and contaminants in the cold air return. You should clean your cold air filter every two months and check the return air for signs of dog hair or even dust.

If you have a ducted roof air conditioning system, the cold air return is usually behind a vented grate in the ceiling and the ductwork is embedded into the ceiling.

To make your roof air conditioner operate at maximum cooling capacity, here are some tips:

1. Make sure your filters are clean and unobstructed. Clean them in lukewarm water with a mild detergent and rinse thoroughly, and then let dry overnight. You can also use an air compressor to blow them out as well.

2. Verify the air return to the AC unit is not clogged with dirt or other contaminants.

3. Check the condenser coil up on the AC unit to verify the coils are not obstructed or pinched and will let the fan blow out hot air to the outside.

4. Make sure you have at least 115 volts of AC going to the unit. Low voltage at the campground source will still allow the unit to operate, but not at maximum capacity.

5. Park in the shade. Getting out of the sun can mean a temperature change of over 20 degrees during hot weather. The roof air conditioner can only cool the ambient inside temperature about 20 degrees, so if it’s 100 degrees inside the rig, you will only be able to cool it down to 80 degrees if everything is working perfect!

6. Keep the window blinds down and windows shut (again, getting the inside to cool down by insulating the windows and not allowing the cool air inside the rig to escape).

7. Limit the use of heat generating appliances such as the stove top, toaster, oven, and even the microwave which will exhaust hot air into the coach.

8. Add fans inside the rig to circulate air help get rid of “pockets” that air sits and gets warm.

9. Develop “zones” that need to be cooled and those that don’t. You may not be able to cool a 40’ rig when the temperature is 110 degrees outside, so close off the bedroom and bathroom and close the ductwork if available and have both air conditioners cooling the living room and kitchen. Then cool the bedroom at night when the temps go down and zone off the living room.

10. Install LED lights as they not only draw about 10 times less power, they run about 10 times cooler.

11. Use the patio awning and window awning to help provide shade and a cooler interior.

12. Install a MaxxAir roof vent cover and bring in cooler air when temperatures are good, and exhaust hot air out during the heat of the day.

Now that you have a better understanding of your rig’s cooling system, hopefully you can use some of these tips to make yourself comfortable. Stay cool!

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23 Responses to ““Cool” Tips to Make Your RV Air Conditioner Run More Efficiently”

    RV Make: Forest River, RV Model: salam, RV Year: 2011, Brand: adding camera to back of 5th wheel

    do wireless cams work or other suggestions

    • Customer Service

      Hello Ronald,

      Wireless backup cameras are a great asset not only for backing up, but for
      seeing what or who is behind you when traveling! I’ve tried a number
      of “cheap” cameras and have not been impressed. They have limited
      field of vision and several only have a distance of about 25 feet for the
      signal. There are some good products on the market such as Furrion,
      Tadibrothers, and Rear View Safety. They have a great camera that is
      weatherproof, long signal distance, and quality monitor which also has
      good night vision. Plus they are easy to install and have limited
      interference from local WiFi and other signals.

      David RVRC Video Membership

    • David

      RV Make: KZ, RV Model: Connect 241RK, RV Year: 2018

      Wireless rear cameras are great for backing into a barn or a parking space. They are also good for monitoring traffic behind you while traveling.

  2. Gary

    RV Make: HIGHLAND RIDGE/Open Range, RV Model: 319rls Light , RV Year: 2015, Brand: Accu-slide, Model Number: Dining room slide-out

    What are the weight Specs. Or limits. And Island position on slide + other weight issues.

  3. Allen

    RV Make: Jayco, RV Model: 25 RKS, RV Year: 2013

    I’m camping in Georgia. Outside temp about 80 degrees. Temp inside my camper 88 degrees. I have good shore power, good battery voltage, clean filters inside, clean fins on roof unit, thermostat seems to be working fine. AC unit is working but blowing air at 87 degrees. Any help would be greatly appreaciated as I’m away from home working out of my trailer.
    Thank you,
    Allen Kingsley

    • Customer Service

      Hello Allen,

      It would appear your compressor is not coming on or not running very long? If the outside temperature is 80 degrees, the inside temperature will be higher and the blower is pulling inside air through the return air and just recycling it so it will get hotter. First, make sure your thermostat is set to cool and low fan. Some have a fan only setting that will not start the roof air, just run the fan to recycle air. Then turn off the thermostat, set it to 70 degrees, turn it to cool and low fan, and the fan should kick on and then you should hear the compressor come on with a vibration and lights dim slightly. If it does not come on, you should test the thermostat by pulling the cover off and jumping the two power wires. Since you did not provide the make, model and year of the rig or the type of thermostat, I can not tell which wires to jump. If the compressor comes on for a short period of time and shuts off, it could be the compressor coils are dirty and not getting air flow. This can only be identified by taking off the roof air cover and cleaning the coils inside.


      RV Repair Club Video Membership

  4. Leroy

    RV Make: Fleetwood, RV Model: Bouncer classic, RV Year: 2012, Brand: Stock mirror ?

    Knocked mirror off in accident, replaced with the same from Fleetwood, when replacing the mirror found I didn’t have any wiring from motor home.

    • Customer Service

      Hello Leroy,

      Could you please provide us with some more information? Are you saying that the wires that go from the motor home to the mirror are missing? What is the year, made, and model of your motor home?


      RV Repair Club Video Membership

  5. theresa

    RV Make: keystone, RV Model: spingdale, RV Year: 2010, Brand: unknown

    NB Ticket#17684 can i cover floor vents when ac is cooling.

    • Customer Service

      Dear Theresa,

      Thank you for your patience. In regards to your question-

      To provide more specific information on the floor vents we need the make, model, and year of your RV. Most RVs have a separate roof AC and furnace system so they do not share a common return air. If that is the case in your RV, you can cover the floor vents and not have an issue with restricted return air flow.

      You can reply with your make,model and year of your RV at rvrepairclub@program-director.net.


      RV Repair Club Video Membership

      We’d love to have you be a part of our community. We are convinced you will enjoy the benefits of becoming a member and having access to the best instructional how to videos and professional tips. We would like to offer you a special promotion for your first-year membership.


  6. Hollie & Gary Przybysz

    RV Make: Montana , RV Model: Big sky, RV Year: 2012, Brand: 5th wheel, Model Number: 3625RE

    How to make the a/c run quietly,black tank

  7. Rick Harrington

    RV Make: Executive, RV Model: 35cb, RV Year: 1984, Brand: Dometic

    A/C does work.

  8. matt.caldwell2201

    RV Make: Country Coach, RV Model: Magna 630, RV Year: 2006, Brand: Dometic, Model Number: 630516.321

    I just bought this Motorhome last month. Now wondering what the “return air filters” look like. Since it’s a fully ducted system with ceiling shapes (mirrors, lights, and wood), where in the world would I be able to find the filters? Thank you for any help you can provide.

    • Customer Service

      Hello Matt,

      It depends on what style air conditioner you have. The standard ones will have a large square plenum just below the air conditioner. It can have two side vents that can be removed to gain access to the filters, one large vent and screws have to be removed to bring it down, one in the front that can be removed or other variations of this. There is also what they call “low profile” AC’s that don’t have a vent directly below the AC, but off to the sides. There will be two in this case. They look like normal vents but the can easily be removed and they will have filters located in them. With any AC, the return filters will be directly below the AC unit. They can off to the side but will be very close to the AC. Search the area directly below and you will find them. I have included a few different styles that are very common in RV’s.

      This is the low profile, there are two and they are on the sides closer to the walls.

      I hope this helps!

      RV Repair Club Video Membership

  9. barry

    RV Make: holiday rambler, RV Model: vacationer, RV Year: 2017

    the kitchen shown in the picture is gorgeous. what motorhome is this in.

  10. davidjames4554

    RV Make: Fleetwood, RV Model: Tioga, RV Year: 2011, Brand: Coleman, Model Number: Mach model# 48208A876

    How hot should the electric motor that pulls air though the condenser get

    • Customer Service

      Dear David,

      Thank you for your patience. In response to your question-
      It may get warm but usually it doesn’t get hot to the touch. There is heat coming out of the condenser and the compartment does get warm so the motor will get a little warm but it shouldn’t be getting real hot. If it does, there could be something binding it up or the motor is failing. There is usually a plastic casing and if there is any warping to it, it has gotten too hot. Again, there will be heat back there and it is pushing it away so it will get hot but it shouldn’t be too hot to touch.

      RV Repair Club Technical Expert

  11. David

    RV Make: KZ , RV Model: Connect 241RK, RV Year: 2018

    Rear cameras are great. They also help watch the traffic behind you if you can’t see them.

  12. Kenny Brooks

    RV Make: Volkswagen, RV Model: Eurovan, RV Year: 2000

    My wifes older (2000) Eurovan Weekender needs new A/C . I want to use a roof top a/c in place of the standard system. Would these cool adequately inside this smaller space than a standard RV? If so what would you choose given out hot/very humid south Alabama summers.. Thanks for any help you may have…

    • Customer Service

      Dear Kenny,

      Thank you for your patience. In response to your question-

      I believe it would work quite well for the smaller area. Usually the smaller AC roof mounted systems are around 13,000 BTU and I would assume that is better that what the standard system was in the Eurovan. I think those were closer to around 9,000 BTU. I do like the Dometic Brisk II AC’s, they are a little louder than other systems but the fan runs faster and gets out the humidity much better which will help cool faster as well. For harsher climates the Dometic Air Command is the best model, it is a lot quieter too just a little bulkier. If you want something smaller and more sleek, I recommend the Penguin model. Anyway you go, I’m sure these models would cool better than what you had before. I hope this helps!Here is some more information on their models:https://www.dometic.com/en-us/us/products/climate/air-conditioners/rv-air-conditioners

      We’d love to have you be a part of our community. We are convinced you will enjoy the benefits of becoming a member and having access to the best instructional how to videos and professional tips. We would like to offer you a special promotion for your first-year membership.


      RV Repair Club

  13. Ami Offenbacher-Ferris

    RV Make: Thor, RV Model: Chateau, RV Year: 1983, Brand: Dometic

    Hi. My unit stopped blowing cool air today and started dripping water on the inside through the air intake screen. Advice please?