Is your RV air conditioner abnormally loud or noisy? RV air conditioners are rather infamous for being irritatingly noisy in general, but if you hear a rattling, buzzing, humming, or other strange sound, then that’s your appliance sounding the warning bell. And remember: An RV air conditioner with low refrigerant generally cannot be recharged.

As I said, RV air conditioners make a lot of “whooshing” noise in general. They move a lot of air through small ducts and obstructed plenums. That’s one reason why many RV owners prefer a fully ducted air conditioner, which is much quieter because all that raging airflow is quietly contained inside the ceiling itself. 

But as for these other noises … they are not normal. Most are due to a mechanical issue, although electrical issues can sometimes manifest as aberrant sounds. DO NOT CONTINUE TO OPERATE an air conditioner that sounds like it ate a breakfast of ball bearings or is trying to hum a high C. Noises are symptoms only. Treat the cause, not the symptom.