Feeling hot in your Airstream? The quality of cooling you get from your rooftop air conditioner depends a lot on what you do. In normal operation, the air conditioner can produce air that’s about 18 to 22 degrees cooler than what goes into it. That means if the interior of the Airstream is 100 degrees, 80-degree output air is about the best you can expect initially. As the air recirculates, the temperature of the output air will drop. To get the best cooling, do what you can to park in shade, and follow these tips:
Close curtains, shades, and blinds. Put insulation to your windows, vent fans and skylights. The “bubble wrap” type of insulation with silver coating works well and can be cut to fit.
If you can’t park in shade, try to park on gravel or grass. Put out your patio awning and window awnings if you have them.
Cook outdoors or use the microwave oven to avoid adding heat to the trailer. Limit use of incandescent lights—each one of them is like a little 10-watt heater.
“The best thing you can do for the long life of your air conditioner is to feed it the proper electrical voltage,” said Rich Luhr, author of Airstream Life’s (Nearly) Complete Guide To Airstream Maintenance. “Low voltage is bad news for the compressor.” Don’t expect your air conditioner to start with less than 103.5 volts, and running it on a day when the campground voltage is less than 108 volts is risky.
It only takes a short “brown out” to drop the voltage below a safe level and cause damage, and it can happen while you aren’t looking. This is one reason why you should have an AC voltage monitor somewhere in your Airstream, or an electrical protection device that cuts off the power when the voltage is too low.
Even newer campgrounds can have voltage problems. If it’s a hot, humid day and everyone is running their air conditioning full blast, be wary and check the voltage. Likewise, don’t run your air conditioner on a household extension cord or a household 15-amp outlet because that will add to the risk of low voltage.
Don’t use an extension cord rated for less than 30 amps (50 amps for Airstreams with two air conditioners), and never use a household (15-amp) outlet. Keep filters, condenser fins, and all other parts clean. “The last two tips are the ones people ignore the most, and that’s a shame because they are really the most important,” writes Luhr.
To maximize the efficiency of the air conditioner, clean dust off the filters regularly. Dust builds up quickly and can severely reduce the amount of cool air you get. Also, dirty filters cut down the amount of air that can circulate and will encourage frost to form on the cooling coil, which means the air conditioner is more likely to ice up.
Depending on the model of air conditioner you may have two knobs and then two screws to drop the shroud (older style), a pair of surface-mounted plastic vents with tabs to release, or a pair of small filters that can be slid out from the front.
Airstreams with ducted air (25-foot and longer trailers starting with model year 2015) have filters located above the return air grills in the ceiling. Replacement filters are available from Airstream dealers, part #382236.
To remove the return air grill on a trailer with ducted air conditioning, just pry it out with a non-marring tool at the short edges of the screen. The filter lies atop the grill.
While you’ve got the filters out, look inside for excessive dust, bugs, cobwebs, or other debris. You can vacuum this out with a brush attachment. Most filters are washable, so you only need to replace them when they can’t be cleaned or when they get torn.
View from the top.
If you want to go further, take a look at the air conditioner from the roof. First, remove the shroud (just a few screws) in order to get a good look at the condenser fins and compressor coils. You can spray the fins with a water hose or compressed air, from the inside out, to clean them up, and bend the fins straight again. There’s a tool called a “fin comb” that can be used for this. Check for mold, wasp nests, and dirt, and clean everything.
If you suspect problems with the air conditioner, it’s probably best to take it to an RV technician. The tech will compare the incoming air temperature to the outgoing air temperature (the “temperature delta”) to see how well the unit is cooling. Other checks include a more thorough inspection of the components, checking the amperage draw, inspecting the condensate drain, the condition of the roof pan and mounting bolts, and perhaps oiling the fan motor.