The smoke alarms are designed to require as little maintenance as possible, but there are simple things you should do to ensure they are always working properly:
Test each smoke alarm after the RV has been in storage, and before every trip. While using your RV, test each smoke alarm at least once a week and keep a supply of 9-volt batteries on hand.
Vacuum any dust off the smoke alarm’s cover with a soft brush attachment, and then test the alarm.
Never use water, cleaners, or solvents that could damage the smoke alarm. When the batteries need to be changed, the unit will start to beep once a minute. Be sure to replace your smoke alarms at least every ten years. The manufactured date code is on the back of the unit.