Camper A/C Not Working? Troubleshooting 5 Common Problems

Nothing can sour a summer camping trip faster than RV air conditioner problems. Whether it’s poor airflow, strange noises, or a unit that won’t work at all, dealing with A/C issues can really put a damper on your adventures. Thankfully, many of the most common problems have simple fixes you can handle yourself.

In this guide, you’ll find simple RV A/C troubleshooting tips and effective solutions to help you stay cool and comfortable on your next trip. And, if your camper A/C is still not working, be sure to check out Parts Via for top-quality parts and accessories that can help get your system back in shape.

1. Warm or Barely Cool Air Flow

There’s nothing worse than returning to your sweltering camper after a long day outdoors, only to crank up the A/C and feel a blast of warm air. If this happens to you, don’t panic—there are a few easy steps you can take before assuming your system’s done for:

• Check the Thermostat Settings: Sometimes the issue is as simple as an incorrectly-set thermostat. Make sure it’s in cooling mode and that the temperature is set lower than the current room temperature.
• Ensure Proper Airflow: Poor airflow can seriously affect your A/C's performance. Check for anything blocking the A/C unit, like debris on the roof or inside the vents. Inside the camper, make sure there’s no furniture, curtains, or other items obstructing the vents, as these can also limit airflow.
• Check the Air Filter: These little guys can easily get clogged with dust and debris, messing with both your A/C’s performance and the quality of the air you’re breathing. If your filter is reusable, give it a thorough cleaning. For single-use filters, consider upgrading to a thicker, aftermarket filter like RV Air. With plenty of options available, you can expect to get about 90 days of use before it’s time to replace.
• Inspect the Coils: Over time, dirt and debris can build up on the evaporator and condenser coils, which can seriously reduce your A/C’s cooling power. Use a soft brush or coil cleaner to gently clean off any gunk.
• Check refrigerant levels: If the refrigerant is low, your A/C will struggle to cool the air effectively. If you suspect this might be the problem, it’s best to call in a professional to recharge the system.

2. Strange Sounds

If your A/C is making odd noises, it’s good to listen up. Here’s what those sounds might mean—and what you can do about them:

• Hissing: A hissing noise could signal a refrigerant leak. If you hear this, it’s likely refrigerant is escaping from the system. You’ll want a professional to take a look.
• Banging or clanking: These sounds may be due to loose parts, like a fan blade or an internal component. Check for loose screws or debris inside the unit and tighten or clean them as needed.
• Rattling or vibrating: This could be coming from a loose fan, motor, or other components. Inspect the fan blades and motor mount for any signs of wear. Tightening or replacing these parts can quiet things down.
• Grinding: A grinding noise usually points to issues with the fan motor or compressor, often caused by a lack of lubrication or damaged bearings. If this is the case, it’s best to call in a professional to handle the repair.

3. Strange Smells

Got some unpleasant odors wafting from your RV air conditioner? Your nose might be picking up on a bigger problem. Here’s what those smells could indicate and how to handle them:

• Musty or moldy smell: Mold and mildew love damp environments—like your A/C’s filters and ducts. Clean or replace your filters, and use an RV-safe disinfectant spray or coil cleaner to freshen up the system.
• Stale, damp odor: A clogged drain line could be trapping moisture and growing bacteria. Clear out the drain line and make sure water is draining properly to keep things fresh.
• Burning smell: If you smell something burning, shut off the A/C immediately. Overheating electrical components or a struggling motor could be to blame. Check for obvious issues, but if the smell persists, call a pro before further damage occurs.
• Sharp, chemical scent: This could signal a refrigerant leak or overheated electrical parts. Either way, it could be serious—get a professional to inspect it as soon as possible.

4. A/C Unit Not Turning On

There’s nothing like flipping the switch on your A/C and getting… nothing. If your camper A/C is not working at all, here are some common culprits and how to fix them:

• Check the power supply: It might sound obvious, but make sure the A/C unit is plugged in and the power switch is on.
• Check the thermostat:Make sure it’s in cooling mode and set lower than the current room temperature. If it seems off, try resetting it or replacing the batteries. Some digital thermostats may need recalibration.
• Try resetting the unit: Some A/Cs have a reset button or can be restarted by turning them off for a few minutes before powering back on.
• Check the circuit breaker:A tripped breaker can cut power to your A/C. Take a peek at your RV’s electrical panel and reset any tripped breakers. If this keeps happening, you could be dealing with a faulty breaker, an A/C issue, or a deeper electrical problem.
• Test the power source: If you’re using shore power or a generator, confirm it’s providing enough electricity to run the A/C.
• Inspect the fuses: A blown fuse can prevent the A/C from turning on. If you find one, swap it out with the correct amperage.
• Check the start capacitor:This component helps the A/C motor kick on. If it fails, the unit won’t start. Replacing the capacitor is usually a job for a professional.
• Look for loose wires: Loose or disconnected wiring inside the A/C unit can prevent it from powering on and pose a fire risk. Make sure all connections are secure, and if you spot an issue but aren’t comfortable handling it, call in a pro.

5. Leaking Water or Ice Formation

If you’re noticing water pooling around your A/C or ice forming on the coils, here are the best steps to take:

• Check airflow: If airflow is restricted, the A/C can’t cool the air effectively, leading to ice and eventually water leaks. Make sure all vents are open and unobstructed, and check the fan for smooth operation. Clean any debris around the vents and replace or clean your air filters to improve airflow and prevent these issues.
• Check the thermostat:Test your thermostat by lowering the temperature and seeing if it responds. If it doesn’t, the thermostat may be malfunctioning or not accurately reading the room temperature, causing the A/C to overcool. Recalibration or a replacement might be necessary to get your system back on track.
• Check drain pan position: Ensure the drain pan is properly installed and aligned with the drain line. This pan collects condensation from the A/C unit, and if it’s damaged or out of place, water may not drain properly, leading to leaks or ice buildup. Adjust or replace the pan as needed to prevent issues.
• Blocked or clogged drain line: The drain line carries condensation away from the A/C unit, but over time, dirt, algae, or mold can clog it. You can often clear minor blockages with compressed air or a long, flexible brush—just be careful not to push the clog further down the line. If the blockage is more severe, it might require replacing the drain line or calling a technician.
• Check/charge refrigerant levels:If your A/C is freezing up, it could be due to low refrigerant. Have a professional check for leaks before recharging the system.
• Leaks in the A/C housing:Inspect the housing and seals for cracks or gaps. Damaged seals can lead to condensation issues, so repair or replace them if needed.

Remember—if it’s a scorcher outside and your RV is parked in the sun, even the most reliable air conditioner can struggle to keep up. Hot and humid conditions force your A/C to work overtime, which could lead to any of the common problems on this list. To help your unit perform its best, keep it clean and well-maintained, check your insulation and weather seals, and whenever possible, park in the shade or use a dehumidifier to reduce moisture in the air.

Time for a New RV A/C? Find Your Perfect Replacement at Parts Via!

Sometimes, an RV air conditioner is simply past the point of repair. If you’re dealing with frequent RV A/C troubleshooting, rising repair costs, or a camper A/C that’s just not working like it used to, it might be time for a replacement. A good rule of thumb? If your unit is over 8-10 years old, you’ll likely start experiencing more frequent headaches as parts wear out. Ongoing problems—like tripped breakers or faulty thermostats—often signal deeper issues that might not be worth fixing.

If this sounds familiar, it might be time to upgrade. In addition to saving you money on repairs, a new RV air conditioner can deliver better cooling and more efficient performance. Parts Via offers a wide range of reliable replacement units to suit your needs. Browse our selection, and start beating the heat today. Don’t forget to check out our FREE ship-to-store option at checkout. Simply send your purchase to a local network dealer for convenient pickup or installation.